Answer is C, just multiply and expand.
$23.40
Since we know how much Olivia spent total, and we know how much she spent on the sunglasses, we just subtract 16.35 from 39.74, and the final answer is 23.40
Yet there is a generally accepted measure for standard of living: average real gross domestic product (GDP) per capita. Let's break it down piece by piece: GDP measures annual economic output — the total value of new goods and services produced within a country's borders.
Answer:
13.187 meters
Step-by-step explanation:
Basically, there are 24 meters for every 91 steps: 
There are x meters for every 50 steps: 

Cross multiply
91x = 1200
Divide both sides by 91 to isolate the variable, x
91x/91 = 1200/91
x = 13.186813