To find the range, you find the biggest and smallest number of the set of numbers.
biggest number = 125
smallest number = 90
Now, the biggest number take away the smallest number is the range.
125 - 90 = 35
range = 35
Explanation:
Roughly one out of every thousand stars that form is massive enough to become a black hole. Therefore, our galaxy must harbor some 100 million stellar-mass black holes. Most of these are invisible to us, and only about a dozen have been identified. The nearest one is some 1,600 lightyears from Earth.
A guyot is a sea mount that has been worn down on the top by wave action. I'm pretty sure that is the answer.