When you multiply two numbers in exponential notation whose bases are the same, you just keep the base the same and add the exponents.
In this case, you have (2^6) * (2^6) = 2^(6 + 6) = 2^12.
We can change the base of 4^6 into 2:
(2^2)^6
Is this the same as 2^12? Well, when we have an expression like that above, we multiply the exponents together, so we get: (2^2)^6 = 2^12.
Therefore, Nicholas is correct.