Answer: 5. 1/2 fraction of a wave comes by each second. 6. 1/10 of the wave comes by each second 7. 3.
Explanation: 5. The formula for frequency is f = 1/t, T being period, so the frequency is 1/2.
Same thing with the 6th question, f=1/10
The 7th question asks about celerity, the wave celerity is the speed c at which the wave moves in the x-direction, is given by c=L/T, with L being the wavelength and T being the period.
Therefore C= 6/3, C= 3.