Answer:
The measured redshift is z =2
Explanation:
Since the object is traveling near light speed, since v/c = 0.8, then we have to use a redshift formula for relativistic speeds.

Finding the redshift.
We can prepare the formula by dividing by lightspeed inside the square root to both numerator and denominator to get

Replacing the given information


Thus the measured redshift is z = 2.
The rock strike the water with the speed of 15.78 m/sec.
The speed by which rock hit the water is calculated by the formula
v=
v=
v=15.78 m/sec
Hence, the rock strike the water with the speed of 15.78 m/sec.
definition of breeder reactors.
These are a type of nuclear reactors which produce more fissile material than they consume
Advantages: Breeder reactors produce Pu-239 which can be extensively used as a nuclear fuel. Also, Pu-239 can absorb neutron to form Pu-240, which is another fertile material.[1]
Don’t trust those links they usually pull up your IP
the answer is d they are essential to all ecosystems