Answer:
B. parents
Explanation:
one of the conclusions from Einsteins relativity theory for his equation E=
(where E is energy, m is mass and C is the speed of light),
is that time moves relative to the observer. Time moves more slowly when the observer is in motion (time dilation), therefore an individual in motion ages more slowly than someone at rest. This in fact happened when astronaut Scot Kelly spent nearly a year on board the international space station and on his return, his twin brother had aged slightly faster than him. In conclusion, if a space trip finds a son or daughter is biologically older than his or her parents, the space trip was taken by the parents.
Answer:
hertz (Hz)
The number of periods or cycles per second is called frequency. The SI unit for frequency is the hertz (Hz).
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.
Answer:
length
Explanation:
SI unit of volume = m^3
SI unit of area = m^2
volume unit / Area unit = m^3 / m^2
i.e, unit of length