The average lifespan of a CleanFreek dishwasher is normally distributed with a mean of 8 years and a standard deviation of 1.9 years. Standard Normal Distribution Table

a. What is the probability that a CleanFreek dishwasher will last longer than 11 years? P(X>11)=

b. What is the probability that a CleanFreek dishwasher will last fewer than 7 years? P(X<7)=

c. What length warranty should be established on the dishwashers so that no more than 1.7% of the units will need to be replaced under warranty? x=

years

Round to 2 decimal places.