Solve the all parts of given problem:
Problem: To pull a crate of mass m across a horizontal frictionless floor, a worker applies a force F, directed at an angle theta above the horizontal. As the crate moves forward a distance d,
Part A: What work is done on the crate by the worker's force?
Part B: What work is done by the gravitational force on the crate?
Part C: What work is done by the normal force on the crate from the floor?
Part D: What is the total work done on the crate?
I want help to find what work is done by the gravitational force on the crate.