A 34-pound crate is pushed across the floor by

Question

a 30-pound horizontal force F1. Aside from
the pushing force and gravity F2, there is also
a 34-pound force F3 exerted upward on the
crate and a 20-pound frictional force F4

What kinds of work do the force F1, F2, F3,
F4 do, respectively?
1. +, 0, 0, 0
2. +, 0, 0, −
3. +, +, 0, 0
4. −, +, −, +
5. +, −, +, −
6. +, 0, +, 0

Answer 1

ghjvnm

Answer 2

The answer is 2.) +,0,0,-

Answer 3

The answer is 1.