If $\displaystyle y=\frac{5x^3}{z}$ what happens to the value of y when both x and z are doubled?

a) y is not changed

b) y is halved

c) y is doubled

d) y is tripled

e) y is multiplied by 4

when both the denominator and numerator are both doubled doesn't it both cancel out and therefore y remains the same?

Thanks in advance