The answer is 6 and a half days
B. it was necessary to see data from more plants before the conclusion could be accepted.
The amplitude of a wave corresponds to its maximum oscillation of the wave itself.
In our problem, the equation of the wave is
![y(x,t)= (0.750cm)cos(\pi [(0.400cm-1)x+(250s-1)t])](https://tex.z-dn.net/?f=y%28x%2Ct%29%3D%20%280.750cm%29cos%28%5Cpi%20%5B%280.400cm-1%29x%2B%28250s-1%29t%5D%29)
We can see that the maximum value of y(x,t) is reached when the cosine is equal to 1. When this condition occurs,

and therefore this value corresponds to the amplitude of the wave.
21. light changes its direction when travelling through a new medium because denser mediums have a higher angle of refraction.
<span>The
formation of the Solar System began 4.6 billion years ago with the
gravitational collapse of a small part of a giant molecular cloud. Most
of the collapsing mass collected in the center, forming the Sun, while
the rest flattened into a proto-planetary disk out of which the planets,
moons, asteroids, and other small Solar System bodies formed.
Hope it helped
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