ANSWER
\(3.95 \times {10}^{12}\)
EXPLANATION
The first number is
\(1.7 \times {10}^{ - 13}\)
The second number is
\(3.5 \times {10}^{25}\)
The product of the above two numbers is
\(1.7 \times {10}^{ - 13} \times 3.5 \times {10}^{25}\)
We regroup the numbers to obtain,
\((1.7 \times 3.5) \times {10}^{ - 13} \times {10}^{25}\)
We now multiply out the expression in the bracket to obtain,
\(3.95 \times {10}^{ - 13} \times {10}^{25}\)
Recall also that,
\({a}^{m} \times {a}^{n} = {a}^{m + n}\)
We apply this property to obtain,
\(3.95 \times {10}^{ - 13 + 25}\)
This finally simplifies to,
\(3.95 \times {10}^{12}\)
Therefore the correct answer is D.
