The heights of plants in Zack's garden are normally distributed with a mean of 15 inches and a standard dev of 1.2 inches. What percent of plants in his garden are: *Answer as a percent without the percentage sign. For example if I thought the answer was 20% I would type "20" rather than 0.20.

a) Between 13.8 and 16.2 inches tall?

b) Shorter than 13.8 inches?

c) Taller than 17.4 inches?

d) Between 13.8 and 17.4 inches?