Pls help ! i’ll give brainliest answer 1.) research 3 different coins. include the county, name of coin, value, composition, other properties

2.) use your research and the picture below to complete the following: write down 3 similarities and 3 differences

I'll ask a buddy o

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.

the answer for sodium is 0.186

the answer for rubidium is 0.251