Answer
a.P(has never shopped on the Internet or is a female)= $\frac{700 + 500}{2000}$ +$\frac{300+500}{2000}$ - $\frac{500}{2000}$ = 0.75
b.P(is a male or has shopped on the Internet)=$\frac{500+300}{2000}$ +$\frac{500+700}{2000}$ - $\frac{500}{2000}$ = 0.75
c. P(has shopped on the Internet or has never shopped on the Internet)=$\frac{300 + 500}{2000}$ +$\frac{500+700}{2000}$ = 1
Work Step by Step
see above.