Question

Which of the following is the best estimate for the mass of all the people living on the Earth? (a) 2 3 108 kg (b) 1 3 109 kg (c) 2 3 1010 kg (d) 3 3 1011 kg (e) 4 3 1012  kg​

Answer 1

Answer:

The population is about 6 billion = 6∗10

9

. Assuming about 100 lb per person = about 50 kg per person (1 kg has the weight of about 2.2 lb), the total mass is about (6∗10

9

)(50kg)=3∗10

11

kg,

answer (d).