The correct answer is 0 degrees.
There's no difference in degrees between an actual temperature of 35 degrees and that temperature combined with a wind speed of 40 mph.
The temperature doesn't change by the effect of the wind speed.
The thermal sensation could change by the effect of the wind speed for another temperatures but if you consult the chart of thermal sensation in function of temperature combined with the wind speed, you can check that a wind speed of 40 mph doesn't change the thermal sensation for a temperature of 35 degrees.