Shawna got 16 items correct
Step-by-step explanation:
To find the percentage of answers or part of total answers we multiply the fraction with the total number of items.
Given
Total items on test = 20
Correct items fraction = 4/5
Then,

Shawna got 16 items correct
Keywords: Percentage, fractions
Learn more about fractions at:
#LearnwithBrainly
In this question, we have to find the complement and supplement of the given angles .
Complementary angles are those angles whose sum is 90 degree and supplementary angles are those angles whose sum is 180 degree.
So to find the complement and supplement angles, we need to subtract the given angles from pi/2 and pi respectively .
a.

b.

Just subtract 622 feet from 486 feet to get the change in elevation. The result will be negative because your friend's house is at a lower elevation than yours.
Now find the mean change in elevation per mile by dividing (486 ft - 622 ft) by 4 miles:
-136 ft
----------- = -34 ft/mile
4 mi