Why is NH3 polar but CH4 non polar

Explanation:

Nitrogen has a lone pair of electrons. That would mean that NH3 is minus at the left end in this case.

 H

:N  H

H

Methane has its Hs 90 degrees (approximately apart.

    H

H  C  H

    H

The pulling forces on the methane cancel each other out. When that happens the chemical is non polar.

the answer is learned

in scientific notation, the value of the  speed of light in a vacuum

  will be written as 2.995 * 10^8. when this value is represented in the form of

  a * 10^b, then, a = 2.995 and b = 8.

the value of the speed of light in a vacuum given above can also be rounded up to approximately 300000000. in this case, the scientific notation will be written as 3 *10^8.