Is an A* possible??

I want to achieve A* for math , physics and CS. Wonder whether it is possible or not. Some said that it's extremely difficult for math. Is this true?? (I'm doing A2 in this may/June series)

I want to achieve A* for math , physics and CS. Wonder whether it is possible or not. Some said that it's extremely difficult for math. Is this true?? (I'm doing A2 in this may/June series)