Answer:
(i) The wavelength is 0.985 m
(ii) The frequency of the wave is 36.84 Hz
Explanation:
Given;
mass of the string, m = 0.0133 kg
tensional force on the string, T = 8.89 N
length of the string, L = 1.97 m
Velocity of the wave is:

(i) The wavelength:
Fourth harmonic of a string with two nodes, the wavelength is given as,
L = 2λ
λ = L/2
λ = 1.97 / 2
λ = 0.985 m
(ii) Frequency of the wave is:
v = fλ
f = v / λ
f = 36.29 / 0.985
f = 36.84 Hz
Answer:
C, weathering by the water.
Explanation:
While in the river, it scraps againsts other rocks and things, which causes it to change shape. For example be smoother and round.
Change in state(from liquid to solid) and change in colour I believe.
The number of electrons in a neutral atom is equal to the number of protons. The mass number of the atom (M) is equal to the sum of the number of protons and neutrons in the nucleus. The number of neutrons is equal to the difference between the mass number of the atom (M) and the atomic number. Therefore, it is true!