The average height of males is 175 cm, with a standard deviation of 7.5 cm. The average height of females is 165 cm, with a standard deviation of 7 cm.

Round answers to 1 decimal place when appropriate.

a. What is the average sum of the heights of one male and one female?

cm

b. What is the standard deviation of that sum?

cm

c. On average, how much taller is a male than a female?

cm

d. What is the standard deviation of the difference in heights?

cm