(a)

Find continuous exponential equation.

If an initial quantity grove or decays at an exponential rate or , then the final amount after a time is given by the following formula .

First year number of computer stores opened is .

After  years number of computer stores is .

Time period years.

So .

Substitute , and in .

Apply logarithm on each side.

Power property of logarithm : .

Apply property of logarithm : .

.

The equation is .

(b)

Find number of stores in the year.

Find time period.

Substitute , and in .

.