13.Suppose you measure the blood pressure of 100 hypertensive males and find that they have a mean systolic blood pressure of 133 mm Hg with a variance of 16 mm Hg. You later discover that your blood pressure monitor was calibrated incorrectly. To adjust for this mistake, you subtract 5 mm Hg from each male's systolic blood pressure. What is the standard deviation of the new data shifted by 5 mmHg?

a.2

b.11

c.4

d.20

e.Cannot be determined without knowing the raw data values for blood pressure