Question

5. Suppose that the volumes of four stars in the Milky Way are 2.7 × 1018 km3, 6.9 × 1012 km3, 2.2 × 1012 km3, and 4.9 × 1021 km3. What is the order of the stars from least to greatest volume?
A.) 2.7 × 1018 km3, 6.9 × 1012 km3, 4.9 × 1021 km3, 2.2 × 1012 km3
B.) 2.2 × 1012 km3, 6.9 × 1012 km3, 2.7 × 1018 km3, 4.9 × 1021 km3
C.) 2.7 × 1018 km3, 6.9 × 1012 km3, 2.2 × 1012 km3, 4.9 × 1021 km3
D.) 2.2 × 1012 km3, 4.9 × 1021 km3, 2.7 × 1018 km3, 6.9 × 1012 km3
I have no idea what the answer is. Please help. Thank You.

Answer 1

To be able to arrange the volumes from least to greatest we must be mindful that the exponent of 10 in the scientific notation should be arranged from least to greatest also. If two or more items have the same exponents in the 10 of the scientific notation, we use the base for comparison. For this item, the arrangement should be        
              2.2x10^12 km³, 6.9x10^12 km³, 2.7x10^18 km³, and 4.9x10^21 km³
Thus, the answer to this item is letter B. 

Answer 2

1) A

2)D

3)B

4)B

5)B

6)A

Just took it. 100%