Answer:
A
Explanation:
The line(A) goes throughout the entire picture. So therefore choice A would be it's length.
Answer:
Explanation:
The x-component is found in the magnitude of the vector times the cosine of the angle.
and, to 3 sig dig,

Answer:
The observed wavelength on Earth from that hydrogen atom is
.
Explanation:
Given that,
The actual wavelength of the hydrogen atom, 
A hydrogen atom in a galaxy moving with a speed of, 
We need to find the observed wavelength on Earth from that hydrogen atom. The speed of galaxy is given by :

is the observed wavelength

So, the observed wavelength on Earth from that hydrogen atom is
. Hence, this is the required solution.
Gravity increased the downward speed (or decreases the upward speed) by 9.8 m/s every second.
21.2/9.8 = 2.2 seconds
Anything times zero is zero