The pressure wave, P = 0.01sin $[1000 t-3 \times] \mathrm{Nm}^{-2}$ , corresponds to the sound produced by a vibrating blade on a day when atmospheric temperature is 0°C. On some other day when temperature is T, the speed of sound produced by the same blade and at the same frequency is found to be 336 ms–1. Approximate value of T is :