Answer: O horizon
Horizons refers to the distinct layers of soil lying parallel to the earth surface. Horizons develop as a result of soil formation. Soil forms as a result of weathering or rocks and addition of organic matter from the decomposition of plant and animal waste. Each horizon differs from the others on the basis of color, texture, type of particles present in the soil, type of minerals present and amount of organic matter present in the soil.
O horizon is the soil horizon that is located closest to the earth's crust. This horizon consist of undecayed or partially decayed animal and plant waste like shedded leaves, bark, animal skin and feces. As, the matter remains undecomposed, therefore, this horizon consists of low amount of organic matter and it is less fertile for plant growth.
Answer:
Time take to fill the standing wave to the entire length of the string is 1.3 sec.
Explanation:
Given :
The length of the one end
, frequency of the wave
= 2.3 Hz, wavelength of the wave λ = 1 m.
Standing wave is the example of the transverse wave, standing wave doesn't transfer energy in a medium.
We know,
∴
λ
Where
speed of the standing wave.
also, ∴ 
where
time take to fill entire length of the string.
Compare above both equation,
⇒
sec

Therefore, the time taken to fill entire length 0f the string is 1.3 sec.
Light travels as transverse waves and can go through the vacuum of space, while sound has longitude waves and needs to travel through something solid. It can’t travel through a vacuum of space like light.
Answer:
it can be called PE or sometimes, there are equations which you can use the letter U.
Explanation:
They're Farther's, Genes.