Answer:
Short of 48 contracts.
Step-by-step explanation:
What trade is necessary to reduce beta to 0.9?
Number of contract to be shortened = (0.9 - 1.2) * 36,000,000 / (900*$250)
= -0.3*36,000,000 / 225,000
= -10,800,000 / 225,000
= -48
As it is of negative value, it should be short of 48 contracts.