<span> The
failure of the anchovy harvest in 1972 was blamed on El Niño.</span>
Yes, but there is only 1 atom like that and is is hydrogen. Hydrogen is the only element that could have a nucleus with one proton and no neutrons exist.
The correct answer is A. Acid rain forms from human activities and lowers the pH of rainwater below 7
Explanation:
The term "acid rain" is used to refer to rainwater with a low pH or a high acidity, this includes rainwater with a pH below 7 (solutions with a pH under 7 are acidic). In terms of formation, acid rain is mainly the result of human activities such as factories or cars that release pollutants into the atmosphere including nitric and sulfuric acids and these alter the natural pH of rain and makes it more acidic. Additionally, acid rain has negative consequences such as the death of fishes and other organisms in lakes, rivers, etc. because the acidity is toxic to many organisms. Thus, acid rain is the result of human activities and it lowers the pH of rain (Option A).
Answer:
The forces that do non-zero work on the block are gravity and normal reaction force
Explanation:
Give that,
The frequency range the dog can hear is 15Hz to 50,000Hz
The wavelength of sound in air at 20°C =?
Speed of sound is 344
The frequency corresponding to the lower cut-off point is the lowest frequency which his 15Hz
F=15Hz
The relationship between the wavelength, speed and frequency is given as
v=fλ
Then,
λ=v/f
λ=v/f
λ=344/15
λ=22.93m
