How did Mendel make the F1 generation for his experiments?

A.
He crossed two F2 generations.

B.
He crossed only round seed plants.

C.
He removed all the smooth seed plants.

D.
He crossed two pure lines.

According the inverse square law, doubling the distance from the source of the sound, a speaker, for example, will drop the sound 6 db each time. if you were standing in the back of an auditorium, 32 feet away from a speaker not using any amplification, would you be able to hear a speaker clearly? why or why not?