For a flight plan filed before flight, the indicated time of departure is:
a. The time overhead the first reporting point after take-off
b. The time at which the flight plan is filed
c. The estimated off-block time
d. The time of take-off
a. The time overhead the first reporting point after take-off
b. The time at which the flight plan is filed
c. The estimated off-block time
d. The time of take-off