Answer
a. P is a square and P is not a rectangle.
b. Today is New Year's Eve and tomorrow is not January.
c. The decimal expansion of r is terminating and r is not rational.
d. n is prime and n is neither odd nor 2.
e. x is nonnegative and x is neither positive nor zero.
f. Tom is Ann's father and either Jim is not her uncle or Sue is not her aunt.
g. n is divisible by 6 and n is either not divisible by 2 or n is not divisible by 3.
Work Step by Step
The negation of "if p then q" is logically equivalent to "p and not q:" ~(p $\rightarrow$ q) $\equiv$ p $\land$ ~q.
For sentences involving AND or OR, recall De Morgan's Laws:
The negation of AND: ~(p $\land$ q) $\equiv$ ~p$\lor$ ~q
The negation of OR: ~(p $\lor$ q) $\equiv$ ~p$\land$ ~q