Option fourth "−48; velocity decreases at rate of 48 miles per hour as the time increases" is correct.
<h3>What is the slope?</h3>
The ratio that y increase as x increases is the slope of a line. The slope of a line reflects how steep it is, but how much y increases as x increases. Anywhere on the line, the slope stays unchanged (the same).

We have a function:
v(t) = 352 − 48t
The above function represents the speed of a plane that is landing in the sky.
The function is a linear function.
On comparing with:
y = mx + c
v(t) = -48t + 352
m = -48 
-48 is the slope and it representing velocity decreases at rate of 48 miles per hour as the time increases.
 
Thus, option fourth "−48; velocity decreases at rate of 48 miles per hour as the time increases" is correct.
Learn more about the slope here:
brainly.com/question/3605446
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