What is the simplified form of -9m^-2*n^5*2m^-3*n^-6

"-9m^-2*n^5*2m^-3*n^-6" simplified down:

The answer to "-9m^-2*n^5*2m^-3*n^-6" (simplified) is: -648 -+-n^5+-

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When rates are expressed as a quantity of 1, such as 2 feet per second or 5 miles per hour, they are called unit rates. if you have a multiple-unit rate such as 120 students for every 3 buses, and want to find the single-unit rate, write a ratio equal to the multiple-unit rate with 1 as the second term.

What do you mean by that?