Find the missing value and please shoe how

20

Step-by-step explanation:

? = 180 - 60 - (180 - 80) = 180 - 60 - 100 = 20

look at the picture.

y-intercept for the function on a picture is 4 → point (0, 4).

y-intercept for the function

is for x = 0. substitute:

y-intercept is 8 → point (0, 8).

i'm assuming that it's c.)   volcanoes built the mountains and earthquakes tore them down.