According to the vsepr model, the arrangement of electron pairs around nh3 and ch4 is a. the same, because in each case there are the same number of electron pairs around the central atom b. different or the same, depending on the conditions leading to maximum repulsion c. different, because in each case there are a different number of atoms around the central atom d. the same, because both nitrogen and carbon are both in the second period e. different, because in each case there are a different number of electron pairs around the central atom

Option "B" is correct.

Explanation:

According to VSEPR theory, There are repulsion forces exists among the bond pair - bond pair or bond pair - lone pair of electrons. In and  , the number of electron pairs are same but methane has all the four bond pairs where in ammonia, three bond pairs and one lone pair exists. And thus there are repulsion forces possible in between the lone pair and bond pair of electrons thus the arrangement of electron pairs around both the molecules is same or different depending up on the conditions leading to maximum repulsion.  

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

wher is the rest of the question