Simplify (3.9 × 10−2)(5.13 × 10−10). Write the final answer in scientific notation.

a) 20.007 × 10−12

b) 2.0007 × 10−11

c) 20.007 × 1020

d) 2.0007 × 1020

To simplify the expression, we multiply the coefficients and add the exponents of the powers of 10.

(3.9 × 10^(-2))(5.13 × 10^(-10)) = (3.9)(5.13) × 10^((-2)+(-10)) = 20.007 × 10^(-12)

The final answer in scientific notation is therefore 20.007 × 10^(-12), which is equivalent to (a) 20.007 × 10^(-12).

To simplify the expression (3.9 × 10^-2)(5.13 × 10^-10), we can multiply the coefficients (3.9 and 5.13) and add the exponents (10^-2 and 10^-10).

Multiplying the coefficients: 3.9 × 5.13 = 20.007

Adding the exponents: 10^-2 + 10^-10 = 10^-12

Therefore, the simplified expression is 20.007 × 10^-12, which is option a) 20.007 × 10^-12.

To simplify the given expression (3.9 × 10^-2)(5.13 × 10^-10), we can use the rules of multiplication with numbers in scientific notation.

Step 1:
Multiply the coefficients (numbers in front of the powers of 10).
3.9 * 5.13 = 20.007

Step 2:
Add the exponents of the powers of 10.
10^-2 * 10^-10 = 10^(-2 - 10) = 10^-12

Step 3:
Write the final answer in scientific notation using the multiplied coefficient from step 1 and the combined exponent from step 2.
The final answer is 20.007 × 10^-12.

Therefore, the correct option is:
a) 20.007 × 10^-12