Answer:

v=343m/s
Explanation:
We have to take into account the expressions

if we assume that 256Hz is the fundamental frequency we have

and for wavelength

hope this helps!!
Height of baby carriage from ground = 21m
Mass of carriage with baby = 1.5 kg
The carriage has potential energy by virtue of its height.
Potential energy = mgh = 1.5×10×21 = 315 J
Hence, potential energy of the carriage is 315 Joule.
"60 kg" is not a weight. It's a mass, and it's always the same
no matter where the object goes.
The weight of the object is
(mass) x (gravity in the place where the object is) .
On the surface of the Earth,
Weight = (60 kg) x (9.8 m/s²)
= 588 Newtons.
Now, the force of gravity varies as the inverse of the square of the distance from the center of the Earth.
On the surface, the distance from the center of the Earth is 1R.
So if you move out to 5R from the center, the gravity out there is
(1R/5R)² = (1/5)² = 1/25 = 0.04 of its value on the surface.
The object's weight would also be 0.04 of its weight on the surface.
(0.04) x (588 Newtons) = 23.52 Newtons.
Again, the object's mass is still 60 kg out there.
___________________________________________
If you have a textbook, or handout material, or a lesson DVD,
or a teacher, or an on-line unit, that says the object "weighs"
60 kilograms, then you should be raising a holy stink.
You are being planted with sloppy, inaccurate, misleading
information, and it's going to be YOUR problem to UN-learn it later.
They owe you better material.
Answer: 0.25 m/s
Explanation: Speed = wavelengt · frequency
v = λf and frequency is 1/period f = 1/T
Then v = λ/T = 5 m / 20 s = 0.25 m/s