The correct choice is Buffers.
Buffers contains both acids and bases in equilibrium.when base is added to buffers, they adjust the pH value by releasing hydrogen ions.when acid is added to buffers, they adjust the pH value by consuming hydrogen ions. hence these substances resist any change in their pH value by releasing or absorbing hydrogen ions.This process keeps the pH value constant.
Answer: We can define the solar constant as a measure of the luminous flux density.
Explanation:
The solar constant or solar constant is the amount of energy radiated at the upper limit of the Earth's atmosphere per unit time perpendicular to the unit surface, at the Earth's mean distance from the sun. Amounts to 1367.7 W / m² ± 6 W / m². The sun's constant includes all kinds of electromagnetic radiation, not just visible light. The average value is 1,368 kW / m2 and changes slightly with solar cycles. The amount of these constant changes over one year and has different benefits.
Answer:

Explanation:
From the question we are told that:
Height 
Radius 
Height of water 
Gravity 
Density of water 
Generally the equation for Volume of water is mathematically given by


Where
y is a random height taken to define dv
Generally the equation for Work done to pump water is mathematically given by

Substituting dv


Therefore




![W=3420.84*0.25[2401-65536]](https://tex.z-dn.net/?f=W%3D3420.84%2A0.25%5B2401-65536%5D)


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Answer:
α = - 1.883 rev/min²
Explanation:
Given
ωin = 113 rev/min
ωfin = 0 rev/min
t = 1.0 h = 60 min
α = ?
we can use the following equation
ωfin = ωin + α*t ⇒ α = (ωfin - ωin) / t
⇒ α = (0 rev/min - 113 rev/min) / (60 min)
⇒ α = - 1.883 rev/min²
To solve this problem we will apply the concepts related to the Doppler effect. The Doppler effect is the change in the perceived frequency of any wave movement when the emitter, or focus of waves, and the receiver, or observer, move relative to each other. Mathematically it can be described as

Here,
=frequency received by detector
=frequency of wave emitted by source
=velocity of detector
=velocity of source
v=velocity of sound wave
Replacing we have that,


Therefore the frequencty that will hear the passengers is 422Hz