Instantaneous velocity is the velocity at a specific instant in time. I bet you are taking Honors Physics.
Answer:

Explanation:
Speed of light is the product of its wavelength and frequency, expressed as
S=fw
Where s represent speed, f is frequency while w is wavelength
Making f the subject of the formula then
f=s/w
Substituting 2.99x10^8 m/s for s and 3.012x10^-12 m for w then

Therefore, the frequency equals to 
<span>The Compound Eye. The arthropod (e.g., insects, crustaceans) eye is built quite differently from the vertebrate eye (and the mollusk eye). Arthropod eyes are called compound eyes because they are made up of repeating units, the ommatidia, each of which functions as a separate visual receptor.</span>
Answer:
artificial: light bulb, flash light, computer screens. natural: sun, stars, fires.