A plastic pipe is negatively charged. What can be inferred about the number of protons and electrons in the plastic pipe ?

massxgravity x heght=weightxheight= pe

4900=490xh

h=10

snell's law

refractve index = sin incidence / sin refraction

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.