Respuesta :

Answer:D)4 x 10^-10

Step-by-step explanation:

The given expression is

(5 x 10^-7) (8 x 10^-4)

Firstly, we would multiply the numbers on the left hand side of the 10. It becomes 5 × 8 = 40

Multiplying the 10's, we would apply the law of indices to the powers of 10. It is expressed as

a^2 × a^3 = a^(2 + 3) = a^6

Therefore,

10^-7 × 10^-4 = 10^(- 7 - 4) = 10^ - 11

The simplified form of each expression in scientific notation would be

40 × 10^ -11

= 4 × 10^ -11 +1

= 4 × 10^ -10