For a self locking lifting machine, the efficiency must be a.50 percent b.100 percent c.more than 50 percent d.107 dynes e.less than 50 percent

For a self locking lifting machine, the efficiency must be a.50 percent b.100 percent c.more than 50 percent d.107 dynes e.less than 50 percent
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e. less than 50 percent
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