Question

1. An object is 70 µm long and 47.66 µm wide. How long and wide is the object in km? (4)

A) 70 000 km long and 47622 km wide.         

B) 7.0 x 10-8 km long and 4.8 km wide 

C) 7.0 x 10-8 km long and 4.766 x 10-8 km wide

D) 0.7 x 10-8 km long and 4.766 x 10-7 km wide 

2. Which one of the following is the longest length? (4)

A) 100 decimeters C) 105 millimeters E) 10-7 nanometers

B) 10-2 centimeters D) 101 meters

Answer 1

1. Converting to km, have $70\mu m = 70\times 10^{-6}m = 70\times 10^{-9}km$ and $47.66\mu m = 47.66\times 10^{-6}m = 47.66\times 10^{-9}km = 4.766\times 10^{-8}km$

Thus, the answer is C.

2. D