Finding solutions to the derivatives 2 and 3 isn't difficult but if you're being asked to solve them using limits thats a different story, the thing I used to do when solvin limits was substitute x - infinity with x = a very large number;
For example 1.
if we think of x being a very large number say 100000, then substitute it and solve it the answer is 1x10^-10 or effectively zero, we can say as x tends to infinity the limit is zero. (even though it is impossible to really divide by infinity)
For question 2 we have a very large number divided by a very large number, adding 3 or subtracting 2 would have a negligible effect, the answer is close enough to 1 that we can say the limit is one.
Hope that helped, good luck for your quiz