To find out how many gallons of water the Amazon River releases into the Atlantic Ocean in one year, we can multiply the number of gallons released per second by the number of seconds in a year.
We know:
- Gallons released per second: \(5.5 \times 10^7\) gallons
- Seconds in a year: \(3.2 \times 10^7\) seconds
Now we can perform the multiplication:
\[ \text{Gallons per year} = (5.5 \times 10^7 \text{ gallons/second}) \times (3.2 \times 10^7 \text{ seconds/year}) \]
Multiplying the coefficients and the powers of ten separately:
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Multiply the coefficients: \[ 5.5 \times 3.2 = 17.6 \]
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Add the exponents (since we are multiplying powers of 10): \[ 10^7 \times 10^7 = 10^{7+7} = 10^{14} \]
Now, putting them together: \[ \text{Gallons per year} = 17.6 \times 10^{14} \]
However, we need to express this result in scientific notation with the appropriate number of significant figures. The coefficient \(5.5\) has 2 significant figures, and \(3.2\) also has 2 significant figures, so our final answer should have 2 significant figures.
We can round \(17.6\) to \(18\) (keeping 2 significant figures) and express the result as:
\[ 1.8 \times 10^{15} \]
Thus, the total number of gallons released into the ocean in one year is:
\[ \boxed{1.8 \times 10^{15}} \] gallons.