LaCrosse Technology is one of many manufacturers of atomic clocks. It makes an atomic

digital watch that is radio controlled and that maintains its accuracy by reading a radio signal

from a WWVB radio signal from Colorado. It neither loses nor gains a second in 20 million

years. It is powered by a 3-volt lithium battery expected to last three years. Suppose the life

of the battery has a standard deviation of 0.3 years and is normally distributed.

= 3 and

= 0.3

a. Determine the probability that the watch's battery will last longer than 3.5 years.