What is 2,100 in scientific notation

2.1 × 10³

Explanation:

In scientific notation we move the decimal place until there is just one number to the left of it in the ones position meaning we would put the decimal in between the 2 and the 1.  To make up for the decimal change we represent it with 10 to a specific power, the power it goes to is how many places we need to move the decimal.  Because in this case we moved it past 3 numbers we will multiply 2.1 by 10 to the 3rd power which will look like this

2.1 × 10³

I hope this helps and please don't hesitate to ask if there is anything still unclear!

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.