The temperature-controlled environment in a hospital intensive care unit is monitored by an intelligent instrument that measures the temperature every minute and calculates the mean and standard...

The temperature-controlled environment in a hospital intensive care unit is monitored

by an intelligent instrument that measures the temperature every minute and calculates the mean and standard deviation of the measurements. If the mean is 75F and

the standard deviation is 2.15F,

(a) what percentage of the time is the temperature less than 70F?

(b) what percentage of the time is the temperature between 73F and 77F?