Answer:
C D F
Explanation:
Taking -40/2, we know our answer must be -20.
Testing each answer choice proves this.
A= 40*1/2, which is equal to 40/2, which is 20.
B= -40*-1/2, again, equaling 20.
C= 40/-2. Since one of our terms is negative, this one is -20.
D= 40*-1/2, again, -20.
E= -1/40*2. This would equal -2/40, using fraction multiplication.
F= -40*1/2, Which is the exact same thing the original question asks.
Thus, our final answer is C, D, and F.