Answer:
He can run 112 yards in 12 seconds
Step-by-step explanation:
Here, we want to know the number of yards he can run in 12 seconds
From the question, we are told that his running rate is 38 yards in 4 seconds
So the number of yards he can run in 12 seconds will be;
38 * 12/4
= 38 * 3 = 114 yards
Yes the graph will show a proportional relationship
we know that
Linear function:
A linear function is a function whose graph is a straight line, that is a polynomial function of degree at most one
For exp: 
Here , we are given

we can see that
x is in denominator
so, this can not be linear function........Answer