Explanation:
It is given that,
Force, F = 30 pounds = 133.4 N
Distance, d = 15 feet = 4.572 m
Time taken, t = 3 minutes = 180 seconds
Lucas's speed is given by the ratio of total displacement divided by total time taken. It is given by :
[tex]s=\dfrac{d}{t}[/tex]
[tex]s=\dfrac{4.572\ m}{180\ s}[/tex]
s = 0.0254 m/s
So, her speed is 0.0254 m/s.
Work done, W = F . d
W = 133.4 N × 4.572 m
W = 609.90 J
or
W = 610 J
Hence, this is the required solution.