1) wavelength is 2
6m is 3 wavelengths so 6 = 3.. to find for one wavelength divide both sides by 3
6 = 3
2(m) = 1(wavelength)
2) amplitude is half of what they've given
2/2 = 1m
3) f = 1/t
time period = 1.5s for 3 wavelengths
time period for one wavelength is 1.5/3 = 0/5
so f = 1/0.5 = 2 Hz