The population of the world was 7.1 billion in 2013, and the observed relative growth rate was 1.1% per year. (a) Estimate how long it takes the population to double. (Round your answer to two decimal places.)

90.91 years

Step-by-step explanation:

If the rate of population of the world was 7.1 billion in 2013, and the observed relative growth rate was 1.1% per year, increase in yearly population = 1.1/100 × 7,100,000,000

= 1.1 × 71,000,000

= 78,100,000

The amount increases by 78.1million every year.

To know how long it will take the population to double.

double of the initial population = 2×7,100,000,000 = 14,200,000,000

Increment per year = 78,100,000

Time it will take for the population to double = 7,100,000,000/78,100,000

= 90.91

≈ 91

This means it will take about 90.91years for the population to double

b.-4 units

all you   do is count how many times you move

i get you, what you should do is think of the positive things that would come out of it. it will make yours parents proud and raise your grade. you should always try and if you can't focus tell the teacher.