The given equation is very confusing, next time please type it correctly. However I believe the correct form of the equation based on other sources is:
Wind chill factor:
W (t) = 33 – {(10.45 + 10 sqrtv - v)(33 - t)}/2204
We are given the following variables:
v = wind speed = 12 m / s
t = air temperature = 15°C
To get the value of the wind chill factor W(t) simply plug in the variables in the equation and calculate:
W (t) = 33 - (10.45 + 10 sqrt(12) - 12)(33 - 15)}/2204
W (t) = 33 – 0.27
W (t) = 32.73