The crowd at a concert lifts a singer to a height of 2.2 m. The crowd uses a total of force of 600 N. How much work has the crowd done?

1320 J

Explanation:

The work done by an object can be found by using the formula

workdone = force × distance

From the question we have

workdone = 600 × 2.2

We have the final answer as

1320 J

Hope this helps you

If the heat engine is a perfect carnot cycle engine, thenefficiency = (t2-t1)/t2   where t1=temperature of cold reservoir ( ° k) = 135            t2=temperature of hot reservoir ( ° k)   = 325thereforeefficiency = (t2-t1)/t2 = (325-135)/325 = 0.5846 = 58%  note: this is the theoretical maximum efficiency of a perfect heat engine.   real-life engines do not achieve this value.

Iwould say the answer is d