Answer:
2.92 KHz
Step-by-step explanation:
We are given that
Length of canal,L=3 cm=

By using 1 m=100 cm
Speed of sound=v=350 m/s
We have to find the fundamental frequency of the canal.
We know that fundamental frequency is given by

By using the formula

f=2916.67 Hz

By using 1 KHz=1000 Hz