Peter always shops at SantaBarbara Groceries(SBG). If someone does wear a mask to SBG, the probability that they do not get COVID-19 is 0.9. On the otherhand, if someone is not wearing a mask, there is a 60% chance that they would get COVID-19. Peter is forgetful and remembers to wear his mask to SBG only 70% of the time.

(a) (3 points) What is the probability that Peter would get COVID-19?

(b) (3 points) Suppose you find out that Peter did not get COVID-19, what is the probability that he wore a mask to the grocery store?

(c) (2 points) You meet Peter at SBG. What is the probability that Peter is either wearing a mask or will not get COVID-19?