Question

Which of the following would be a reasonable estimate for the weight of a pencil?
a:1 × 1020 lb
b:1 × 102 lb
c:1 × 10-2 lb
d:1 × 10-20 lb

Answer 1

D, because 10-20=-10, so it would be -10 lbs.

Answer 2

Seems reasonable :)

Answer 3

'C. 1 × 10^-2 lb' Is correct.

'D. 1 × 10^-20 lb' Would be too small for the weight of a pencil.