3. (30 points). You go on vacation and return to find a wind tunnel in your lab is filled with a mystery gas that is either nitrogen (k = 1.400) or

helium (k = 1.667). Your colleague has left you a post-it note saying that she determined the temperature to be 293 K, the Mach number to be 1.2, and the wind speed to be 1208 m/s. (a) Which gas fills the wind tunnel? (b) What would the wind speed be if the wind tunnel was filled with the other gas?