The function of the population is , where (in millions of people) in year .

(a)

When will the population of the United States be  million people.

Substitute in .

Apply logarithm one to one property : if ,then .

Therefore,the population of the United States will be  million people in .

(b)

When will the population of the United States be million people.

Substitute in .

Apply logarithm one to one property : if ,then .

Therefore,the population of the United States will be million people in .

(a) The population of the United States will be  million people in .

(b) The population of the United States will be million people in .