The frequency `f` of vibrations of a mass `m` suspended from a spring of spring constant `k` is given by `f = Cm^(x) k^(y)` , where `C` is a dimensionnless constant. The values of `x and y` are, respectively,
A. `(1)/(2) , (1)/(2)`
B. ` -(1)/(2) , -(1)/(2)`
C. `(1)/(2) , - (1)/(2)`
D. `- (1)/(2) , (1)/(2)`