Question

What is the frequency corresponding to a period of 8.01 s?

Answer 1

The frequency of an oscillation is equal to the reciprocal of the period:
$f= \frac{1}{T}$
where
f is the frequency
T is the period

In our problem, the period is T=8.01 s, therefore the corresponding frequency is
$f= \frac{1}{8.01 s}=0.12 s^{-1} = 0.12 Hz$