Question

PLEASE HELP THIS IS MY LAST QUESTION!

Answer 1

☆Concept:-

The Question is based on the law of exponents .

The law to be used in this question is

$\boxed{\sf a^m\times a^n=a^{m+n}}$

Solution:-

$\\ \tt\longmapsto (9\times 10^{-4})^2$

$\\ \tt\longmapsto 9^2\times 10^{-4(2)}$

$\\ \tt\longmapsto 81\times 10^{-8}$

• Simplify

$\\ \tt\longmapsto 8.1\times 10^{-7}$

Answer 2

Answer:

It is 8.1 × 10^-7

Step-by-step explanation:

${(9 \times {10}^{ - 4} )}^{2} \\ = \{{9}^{2} \times {10}^{( - 4 \times 2)} \} \\ = 81 \times {10}^{ - 8} \\ = 8.1 \times {10}^{ - 7}$