A) is 2x
b) is

c) is -2x
I think these are correct.
![log_{10}1000^{x] = log_{10}10^{2x}=2x](https://tex.z-dn.net/?f=log_%7B10%7D1000%5E%7Bx%5D%20%3D%20log_%7B10%7D10%5E%7B2x%7D%3D2x)
I did similar things to get other answers

Taking the square root of both sides gives two possible cases,

or

Recall that

If
and
, we have

so in the equations above, we can write

Then in the first case,


(where
is any integer)


and in the second,




Then the solutions that fall in the interval
are

It will take her 51.4 minutes.
Explanation:
You would do 12/7 and then multiply that answer by 30.
Order what numbers from least to greatest
27, just multiply30 by 9/10