The time required to prepare a certain specialty coffee at a local coffee shop is uniformly distributed between 25 and 45 seconds. Assuming a customer just ordered one of these specialty coffees, determine the probabilities described below.

a. What is the probability that the preparation time will be more than 28 seconds?

b. What is the probability that the preparation time will be between 30 and 40 seconds?

c. What percentage of these specialty coffees will be prepared within 36 seconds?

d. What is the standard deviation of preparation times for this specialty coffee at this shop?