Math formula for speed, wave leghth and frequency

Hello – you just helped me with my son’s homework.  could you please show me the detial math steps to get the answers, so I can reteach him.  thanks 

A)

at 67F^0 the velocity of sound wave is 343.21m/s.

B)

V=wavelength*frequency

wavelength= v/frequency

wavelength= 343.21/232

wavelength= 1.479m

C)

at 62F^0 the velocity of sound is approximately 340.27m/s

frequency=v/wavelength

frequency= 340.27/18.5

frequency= 18.3929Hz freeslots dinogame telegram营销