29) which of the following molecules is polar?

a) SF6

b) BrF5

c) PF3

d) PF5

e) none of the above

21) For a lewis structure that obeys the octet rule, what is the format change of the central atom of the ion NO3^-1?

a) +1

b) +2

c) -1

d) 0

e) -2