The amount of a radioisotope remaining undecayed after a time equal to four times its half life, will be __________ percent. (A) 3.125 (B) 6.25 (C) 12.50 (D) 25

The amount of a radioisotope remaining undecayed after a time equal
to four times its half life, will be __________ percent.
(A) 3.125
(B) 6.25
(C) 12.50
(D) 25
by

1 Answer

Answer :

(B) 6.25
by

Related questions

The half life of radioactive isotope is 3 hour. If the initial mass of isotope were 256 g, the mass of it remaining undecayed after 18 hr is a)12 g b)

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Why is there no formula to compute the half-life of any given radioisotope?

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If you sell all the capacity on a production line, Capstone interprets this as a. a liquidation instruction and will sell your remaining inventory for one third of the average cost of production. b. a liquidation instruction and will sell your remaining inventory for half the average cost of production. c. a liquidation instruction and will sell your remaining inventory for 65 percent of the production cost.

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What percent is 25 of 125?

Description : What percent is 25 of 125?

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Bhuvana bought 50 dozen of bangles at Rs5 per dozen. She spend Rs.125 on a particular tax and she sold them at 50p per each bangle. What was her profit or loss percent?

Description : Bhuvana bought 50 dozen of bangles at Rs5 per dozen. She spend Rs.125 on a particular tax and she sold them at 50p per each bangle. What was her profit or loss percent?

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Find the flux density of a sheet of charge density 25 units in air. a) 25 b) 12.5 c) 6.25 d) 3.125

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The average domestic investment in the year 2011 is what percent of the average investment in Transport during the given four years? a) 201% b) 65.34% c) 125.45% d) 147.97% e) 167.23%

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In a shell and tube heat exchanger, the height of 25 percent cut baffles is equal to (where, D = inside diameter of shell). (A) 0.25 D (B) 0.50 D (C) 0.75 D

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The conversion of caprolactam in the above case is about __________ percent. (A) 25 (B) 50 (C) 70 (D) 90

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Last Answer : (D) 90

Overall thermal efficiency of a lumpy coal fired suitably designed heating furnace, if operated & maintained properly may be about __________ percent. (A) 10-15 (B) 25-30 (C) 45-50 (D) 65-70

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Last Answer : (B) 25-30

Carbon Content by weight in air dried wood may be about __________ percent. (A) 10 (B) 25 (C) 50 (D) 80

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Yield of charcoal in high temperature carbonisation of wood is about __________ percent. (A) 10 (B) 25 (C) 50 (D) 75

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Nitrogen content of calcium ammonium nitrate (CAN) is __________ percent. (A) 10 (B) 25 (C) 50 (D) 80

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Concentration of NaOH solution produced by mercury electrolytic cell is about __________ percent. (A) 10 (B) 25 (C) 50 (D) 98

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Concentration of NaOH solution produced by diaphragm electrolytic cell is about __________ percent. (A) 10 (B) 25 (C) 50 (D) 98

Description : Concentration of NaOH solution produced by diaphragm electrolytic cell is about __________ percent. (A) 10 (B) 25 (C) 50 (D) 98

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High relative humidity decreases the evaporative process and as the temperature is increased, the relative humidity decreases. The comfort range for human body is the ambient temperature of 22 to 27°C with relative humidity ranging from __________ percent. (A) 5 to 10 (B) 15 to 25 (C) 45 to 50 (D) 75 to 80

Description : High relative humidity decreases the evaporative process and as the temperature is increased, the relative humidity decreases. The comfort range for human body is the ambient temperature of 22 to 27°C with relative humidity ranging from __________ ... to 10 (B) 15 to 25 (C) 45 to 50 (D) 75 to 80

Last Answer : (C) 45 to 50

The average of 12 numbers is 7.9. The average of 5 of them is 6.8, while the average of other five is 7.7. what is the average of the remaining 2 numbers? A) 10.25 B) 11.15 C) 12.65 D) 13.25

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A officer undertakes to complete a job in 250 days. He employs 300 male for 50 days and they complete 1/2 of the work . He then reduces the number of male to 100, who work for 120 days, after which there are 20 days holidays. How many male must be employed for the remaining period to finish the work? a) 25 b) 50 c) 45 d) 35

Description : A officer undertakes to complete a job in 250 days. He employs 300 male for 50 days and they complete 1/2 of the work . He then reduces the number of male to 100, who work for 120 days, after which there ... male must be employed for the remaining period to finish the work? a) 25 b) 50 c) 45 d) 35

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The amount of benzene present in pure Benzol is about __________ percent. (A) 30 (B) 50 (C) 70 (D) 90

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Last Answer : (C) 70

The term total milk solids describes the remaining ____ percent of milk. a. 10–11 c. 5–7 b. 12–13 d. 8–9

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Last Answer : b. 12–13

The total sulphur content of the body is (A) 25–50 gm (B) 50–75 gm (C) 100–125 gm (D) 150–200 gm

Description : The total sulphur content of the body is (A) 25–50 gm (B) 50–75 gm (C) 100–125 gm (D) 150–200 gm

Last Answer : Answer : D

If minimum Rs.1000 is not deposited in Sukanya Samriddhi Account in a financial year, account will become discontinued and can be revived with a penalty of _______ per year. A. Rs.50 B. Rs.100 C. Rs.25 D. Rs.75 E. Rs.125

Description : If minimum Rs.1000 is not deposited in Sukanya Samriddhi Account in a financial year, account will become discontinued and can be revived with a penalty of _______ per year. A. Rs.50 B. Rs.100 C. Rs.25 D. Rs.75 E. Rs.125

Last Answer : A. Rs.50 Explanation: In Sukanya Samriddhi Account, if minimum Rs 1000/- is not deposited in a financial year, account will become discontinued and can be revived with a penalty of Rs 50/- per year with minimum amount required for deposit for that year.

A flywheel connected to a punching machine has to supply energy of 400 Nm while running at a mean angular speed of 20 rad/s. If the total fluctuation of speed is not exceed to in kgm 2 is 1. 25 2. 50 3. 100 4. 125

Description : A flywheel connected to a punching machine has to supply energy of 400 Nm while running at a mean angular speed of 20 rad/s. If the total fluctuation of speed is not exceed to in kgm 2 is 1. 25 2. 50 3. 100 4. 125

Last Answer : 1. 25

A steel bar 5 m × 50 mm is loaded with 250,000 N. If the modulus of elasticity of the material is 0.2 MN/mm2 and Poisson's ratio is 0.25, the change in the volume of the bar is: (A) 1.125 cm3 (B) 2.125 cm3 (C) 3.125 cm3 (D) 4.125 cm

Description : A steel bar 5 m × 50 mm is loaded with 250,000 N. If the modulus of elasticity of the material is 0.2  MN/mm2  and Poisson's ratio is 0.25, the change in the volume of the bar is:  (A) 1.125 cm3 (B) 2.125 cm3 (C) 3.125 cm3 (D) 4.125 cm

Last Answer : (C) 3.125 cm

For determine the specific gravity of soil solids, using a pycnometer of 500 cc., the following data is available : Weight of dry empty pycnometer = 125 g Weight of dried soil and pycnometer = 500 g Weight of dried soil and distilled = 850 g water filled in pycnometer up to top The specific gravity of soil solids, is (A) 2.0 (B) 2.25 (C) 2.50 (D) 2.75

Description : For determine the specific gravity of soil solids, using a pycnometer of 500 cc., the following data is available : Weight of dry empty pycnometer = 125 g Weight of dried soil and pycnometer = 500 g Weight of dried soil and distilled ... of soil solids, is (A) 2.0 (B) 2.25 (C) 2.50 (D) 2.75

Last Answer : (C) 2.50

The slump recommended for mass concrete is about (A) 25 mm to 50 mm (B) 50 mm to 100 mm (C) 100 mm to 125 mm (D) 125 mm to 150 mm

Description : The slump recommended for mass concrete is about (A) 25 mm to 50 mm (B) 50 mm to 100 mm (C) 100 mm to 125 mm (D) 125 mm to 150 mm

Last Answer : Answer: Option A

The concrete slump recommended for beams and slabs; is (A) 25 to 50 mm (B) 25 to 75 mm (C) 30 to 125 mm (D) 50 to 100 mm

Description : The concrete slump recommended for beams and slabs; is (A) 25 to 50 mm (B) 25 to 75 mm (C) 30 to 125 mm (D) 50 to 100 mm

Last Answer : Answer: Option C

The concrete slump recommended for columns, is (A) 25 to 50 mm (B) 25 to 75 mm (C) 75 to 125 mm (D) 50 to 100

Description : The concrete slump recommended for columns, is (A) 25 to 50 mm (B) 25 to 75 mm (C) 75 to 125 mm (D) 50 to 100 mm

Last Answer : Answer: Option C

The concrete slump recommended for foundations, is (A) 25 to 50 mm (B) 30 to 125 mm (C) 50 to 100 mm (D) 75 to 125 mm

Description : The concrete slump recommended for foundations, is (A) 25 to 50 mm (B) 30 to 125 mm (C) 50 to 100 mm (D) 75 to 125 mm

Last Answer : Answer: Option C

The Minimum amount of steel for Main reinforcement in slab should be (Fe 415- grade of steel) [ A ] 0.12 percent of gross cross sectional area [ B ] 0.15 percent of gross cross sectional area [ C ] 0.20 percent of gross cross sectional area [ D ] 0.25 percent of gross cross sectional area.

Description : The Minimum amount of steel for Main reinforcement in slab should be (Fe 415- grade of steel) [ A ] 0.12 percent of gross cross sectional area [ B ] 0.15 percent of gross cross sectional area [ C ] 0.20 percent of gross cross sectional area [ D ] 0.25 percent of gross cross sectional area.

Last Answer : [ A ] 0.12 percent of gross cross sectional area

What percent of a day in 12 hours? a) 25 b) 60 c) 45 d) 20 e) 50

Description : What percent of a day in 12 hours? a) 25 b) 60 c) 45 d) 20 e) 50

Last Answer : Answer: E  Total hours in a day = 24 Required percent = 12/24 ×100  = 50%

A, B and C are 3 partners in a business. Their investments are respectively Rs 2000, Rs 4,000 and Rs 3,000. A gets 30% of total profit for managing the business. The remaining profit is divided among them in the ratio of their investments. At the end of the year, the profit of Ais Rs 1100 less than the sum of the profit of B and C. What amount of income will C get? A) Rs 2100.75 B) Rs 2887.5 C) Rs 2705.75 D) Rs 2546.25

Description : A, B and C are 3 partners in a business. Their investments are respectively Rs 2000, Rs 4,000 and Rs 3,000. A gets 30% of total profit for managing the business. The remaining profit is divided among them in the ratio ... of income will C get? A) Rs 2100.75 B) Rs 2887.5 C) Rs 2705.75 D) Rs 2546.25

Last Answer : Answer: B) The ratio of profit of A, B and C is 2000:4000:3000=2:4:3. Let the annual profit be P. Then, A will get 0.3p for managing the business. And, remaining 0.7p will be distributed in the ratio of their ... ⇒ 7/9 0.7p−2/9 0.7p−0.3p=1100 ⇒ p=12,375 So, C's share=3/9 0.7p=Rs 2887.5

Supriya invests 35% of her monthly salary in insurance policies. She spends 45% of her monthly salary in shopping and on household expenses. She saves the remaining amount of `25,750. What is Supriya's monthly income? a) 128750 b) 160050 c) 205200 d) 263400 e) 391800

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Last Answer : Answer: A  Percentage savings of Supriya = 100 – (35 + 45)  = 20%  Let her monthly income be x  x X 20 /100 = 25750  x = 25750 × 100/20  x = 128750

The radioisotope used to study the thyroid gland is (A) Iodine (B) Cobalt (C) Iron (D) Carbon

Description : The radioisotope used to study the thyroid gland is (A) Iodine (B) Cobalt (C) Iron (D) Carbon

Last Answer : (A) Iodine

A shopkeeper bought 30 kg of wheat at the rate of Rs 45 per Kg. He sold 40% of the total quantity at the rate of Rs 50 per Kg. Approximately, at what price per Kg should he sell the remaining quantity to make 25 per cent overall profit? 1. Rs 54 2. Rs 52 3. Rs 50 4. Rs 60

Description : A shopkeeper bought 30 kg of wheat at the rate of Rs 45 per Kg. He sold 40% of the total quantity at the rate of Rs 50 per Kg. Approximately, at what price per Kg should he sell the remaining quantity to make 25 per cent overall profit? 1. Rs 54 2. Rs 52 3. Rs 50 4. Rs 60

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The average age of 160 boys in a class is 58 yrs. The average group of 30 boys in the class is 42 yrs and the average of another group of 50 boys in the class is 36 years. What is the average age of the remaining boys? A) 72.58 B) 74.25 C) 77.75 D) 75.68

Description : The average age of 160 boys in a class is 58 yrs. The average group of 30 boys in the class is 42 yrs and the average of another group of 50 boys in the class is 36 years. What is the average age of the remaining boys? A) 72.58 B) 74.25 C) 77.75 D) 75.68 

Last Answer : C) Total age of 160 boys = 160* 58= 9280 total age of 30 boys = 30 * 42= 1260 total age of next 50boys = 50 * 36= 1800 average of the remaining boys = [(9280-{1260+1800})/[160 - (30 + 50)] =>9280-3060/80 =>6220/80 =77.75yrs