1. Frequency: 
The frequency of a light wave is given by:
where
is the speed of light
is the wavelength of the wave
In this problem, we have light with wavelength
Substituting into the equation, we find the frequency:
2. Period: 
The period of a wave is equal to the reciprocal of the frequency:
The frequency of this light wave is (found in the previous exercise), so the period is:
Because it is not a good conductor of heat. so the answer is D.
We are given with 98 Newton weight of an object on the surface of the earth with an acceleration equal to 9.8 m/s2. This means the mass of the object is equal to 98/9.8 or 10 kg. Hence the weight of the object 10,000 kilometers above sea level where acceleration is 1.49 m/s2 is 14.9 Newtons.
All meteorites come from inside our solar system. Most of them are fragments of asteroids that broke apart long ago in the asteroid belt, located between Mars and Jupiter. Such fragments orbit the Sun for some time–often millions of years–before colliding with Earth
