The blood pressure in millimeters was measured for a large sample of people. The average pressure is 140 mm, and the sd of the measurements is 20 mm. The histogram looks reasonably like a normal curve. Use the normal curve to estimate the following percentages. 
a. 20.9% 
b. 29.1% 
c. 41.8% 
d. 70.9% 
e. 68.27%