Of course it's possible, because it means that sintheta=-2/5 which satisfies this -1<=sintheta<=1
D.- Food production grew much more quickly than Malthus predicted
Answer:
Most revolutions start because a certain group finds something unjust. For example, the French revolution basically started because the French people believed their government to be unjust. So, for a revolution to be a success would be for that particular group to change what they saw as wrong.
Hope this helps :)