Answer:
4
Step-by-step explanation:
We'll do two things here. First remember that when a number is raised to an exponent, and the result is raised to another exponent, you can simply multiply those exponents and apply them to the base. So we can multiply -1/2 and -2/3, giving us 1/3, which is what we'll raise 64 to.
The other thing to remember is that a fractional exponent is the same as a root of that base. So raising a number to the power of 1/3 just means we want the cube root of that number.
Applying those and we get: