The definition is a nuclear reactor that generates more fissile material than it consumes.

i don't know what symbol ya'll use for wavelength so i just put the word instead.We use the greek symbol lambda.So just plug in everything you know.
wavelength=4.257×10^-7x10^-2 and
v=speed of light = 3×10^8
So you should get f= 7.04 ×10^15Hz
Answer: Varying amounts of the Moon's lit surface being visible from Earth.
Explanation:
Phases of the moon can be defined as the different shapes of the moon visible from the Earth. This happens because sun lits up the face of moon and due to different position of moon in the orbit around earth, varying portion of the lit surface of the moon is visible from Earth. Refer to the diagram below:
Answer:
Inverse Square Law Newton proposed the Inverse Square Law. The effect of gravity (and also on forces such as sunlight) works like this. If say we have a half-mass Earth, it would produce a gravity of not half but a quarter (the square of 2).