Which of the following can be calculated when given the radius of a wheel and the radius of an axle?
a. the effort force needed to move the wheel and axle.
b. the amount of resistance force the wheel and axle can overcome.
c. the mechanical advantage of the wheel and axle.
d. the increase in effort force.

i think its c if i'm wrong

the best answer for these questions would be:

1.            c. is smaller

2.            d) concrete operational

3.            b) interaction with the environment – the children interact with their environment can them learn more.

4.            a) parents who reason openly with children can limit a child’s cognitive ability.