In order to calculate the work done by the person, you use the following formula:
W = Fd (1)
where F is the force exerted on the book and d is the distance on which the distance was applied.
F = 50N
d = 2m
By replacing the values of the previous paramters in the equation (1) you have:
W = (50N)(2m ) = 100J
Then, the work dne by the person was 100J
