How do the densities of crystalline and amorphous polymers of the same material that have identical molecular weights compare?

c. because step up transformer steps up the input voltage i.e increases the input voltage  

the number of turns are greater on the secondary side of step up transformer  

transformer does not handle dc current

i think it's letter a.

the answer is a! (2.9 x 10^-18 j) hope i could someone. : )

it is reliable if two scientists recorded it