In a string of length L, the wavelength of the n-th harmonic of the standing wave produced in the string is given by:

The length of the string in this problem is L=3.5 m, therefore the wavelength of the 1st harmonic of the standing wave is:

The wavelength of the 2nd harmonic is:

The wavelength of the 4th harmonic is:

It is not possible to find any integer n such that
, therefore the correct options are A, B and D.
Answer:
The formation of a rainbow is more a demonstration of the wave-like behavior of light.
Explanation:
A rainbow is caused by the interaction of sunlight with atmospheric conditions. A rainbow formation results from the refraction and reflection of light due to changes in the light's wavelength direction. Naturally, light enters a water droplet, slowing down and bending as it goes from air to denser water in a refraction as if "bent." Then light reflects off the inside of the droplet, separating into its component wavelengths or colors. With light exiting from the droplet, a rainbow is formed.
Answer: Jomo Kenyatta
Explanation: Jomo Kenyatta was an anti-colonial activist and politician and was the first Prime Minister of Kenya. He then served as president of the country from 1964 to his death in 1978