Answer:
The work done on the suitcase is, W = 1691 J
Explanation:
Given data,
The force on the suitcase is, F = 89 N
The distance Russell dragged the suitcase, S = 19 m
The work done on the suitcase by Russell is equal to the work done on the suitcase to overcome the friction
The work done on the suitcase by Russell is given by the formula
W = F · S
Substituting the given values,
W = 89 N x 19 m
W = 1691 J
Hence, the work done on the suitcase is, W = 1691 J
Answer:
Friction. Have a great day! Think positive <3
As we know that speed of sounds is given as

here we know that
t = 23 degree C
now from above equation we will have


now we also know that distance between two consecutive resonance length is half of the wavelength



now we know that


so frequency will be 786 Hz