Answer:
A (-439)
Explanation:
To find the value of (s•t)(-7), we need to first evaluate s(t(-7)) which means we substitute -7 for x in the function t, and then substitute the resulting value in the function s.
So, we have:
t(-7) = 3(-7) = -21
s(-21) = 2 - (-21)^2 = 2 - 441 = -439
Therefore, the value of (s•t)(-7) is -439, which corresponds to option A.
So, the correct answer is A(-439).