To find the range of the cost function \( c = 30.75u + 5.75 \) for the given number of uniforms \( u \) (which ranges from 8 to 12), we can calculate the cost at the minimum and maximum values of \( u \).
First, we calculate the cost when \( u = 8 \):
\[ c = 30.75(8) + 5.75 \] \[ c = 246 + 5.75 \] \[ c = 251.75 \]
Next, we calculate the cost when \( u = 12 \):
\[ c = 30.75(12) + 5.75 \] \[ c = 369 + 5.75 \] \[ c = 374.75 \]
Now, we find the range of \( c \) when \( u \) varies from 8 to 12. The minimum cost occurs at \( u = 8 \) and is \( c = 251.75 \), while the maximum cost occurs at \( u = 12 \) and is \( c = 374.75 \).
Thus, the range of the function for the situation specified (number of uniforms from 8 to 12) is:
\[ { 251.75, 282.50, 313.25, 344.00, 374.75 } \]
So the correct answer is:
d. \(\left{251.75,\ 282.50,\ 313.25,\ 344,\ 374.75\right}\)