Answer with positive exponent =
or 
Answer with negative exponent = 
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Explanation:
The rule we use is

If we multiply two exponential expressions with the same base, then we add the exponents.
The base for each is 5. The exponents 4 and -7 add to -3.
This means

To convert to a positive exponent, we apply the reciprocal to the base. We go from 5, aka 5/1, to 1/5.
So, 
Nate's package is 8 kilograms. This is because, if there are 1,000 grams in 1 kilogram, 8,000/ 1,000= 8 Therefore, the mass of his package is 8 kilograms.
Have a Merry Christmas!
115.5 ft
cut the shape into a square and triangle.
square: 9 x 11= 99
triangle: (6x11)/4 =16.5
99+16.5=115.5