During a physics project, students measure the distance to a tall building across a lake using echoes. They stand at the water's edge when the air temperature is 15∘C, for which the speed of sound is 340m s−1. They clap and record the time interval of 3.40s between the sound and its echo. The next morning the temperature drops to 5∘C. The speed of sound decreases by 0.6m s−1 for every 1∘C fall in temperature. Answer the following.
a. (a) Calculate the distance to the building from the students' position using the first observation.
b. (b) Determine the speed of sound in air at 5∘C.
c. (c) If the students repeat the clap at 5∘C without changing their position, find the new time interval between the clap and its echo.