Question

calculate the period of a wave whose frequency is 5 Hertz and whose wavelength is one centimeter give your answer in a decimal form

Answer 1

The period of the wave is the reciprocal of its frequency.

1 / (5 per second) = 0.2 second .

The wavelength is irrelevant to the period. But since you
gave it to us, we can also calculate the speed of the wave.

Wave speed = (frequency) x (wavelength)

= (5 per second) x (1cm) = 5 cm per second