The function f(x)=5000(0.98)^0.3x

represents the number of white-blood cells, per cubic millimeter, in a patient x days after beginning treatment for a virus.

What is the average decrease per day in white-blood cells per cubic millimeter between days 1 and 5?

a.)​ −29.75 mm^3/day
​b.)-34.75 mm^3/day​
c.)-282.47 mm^3/day
d.-)353.08 mm^3/day