3 experiments are conducted to measure the speed of sound. In the 1st experiment, a loud sound is heard by an observer 100m away at 1 atmosphere of pressure and 20 degrees celcius.

Later, the 2nd experiment is conducted at the same distance and temperature BUT the pressure is 0.95 atmospheres. The 3rd and last experiment is conducted at same distance, a pressure of 1 atmosphere (same as experiment 1) BUT this time the temperature is 25 degrees celcius.

Which experiment recorded the fastest speed: (a) Experiment 1 or (b) All experiments are the same or (c) Experiment 2 or (d) Experiment 3