Answer:
8,146 x 121
Step-by-step explanation:
This is a problem in which you need to measure your understading of "orders of magnitude."
If the estimated answer is
that means that we are looking at a multiplication in the "order of" 
You need to look at the "orders of magnitude" of the things you're multiplying. In the first case, we have
that would be "of the order of"
times
. So the whole multiplication would "of the order of"
or near 
The correct answer, 8,146 x 121, is because it's "of the order of"
times
and the gives us the
we need.
A graphing calculator or spreadsheet program can do this for you. Below is a plot from the Desmos on-line graphing calculator.
135.9 rounded to the nearest tenth
Answer:
2 units. Hope this helps!