If anyone knows how to do this please help. Teacher is a * and we get a 0 on the final if we miss a question

I'll give brainliest if you answer right : )

45 was divided by a power of ten to get 4.5. what power of ten was it divided by? people 4.5

Ahiker stands at an unknown elevation before he ascends 2 miles up a mountain to an elevation of 9 miles. find the elevation of the hiker before his ascent.