What does the slope of the line on displacement/graph represent?

the answer is f1 and d2 because if you put equal force on those two points the beam would balance trust me on this

electric field is a function of 1/r^2

yes, the force per unit charge for a point charge is inverse square law.

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.