B. because no one country has a distinct advantage over the others
-.777 is rational because it can be put into a fraction : -777 / 1000
1/11 is rational because it is a fraction
The square root of 49 is rational because it equals 7 which is a whole number and can be put into a fraction.
The square root of 200 is irrational because it cannot be put into a fraction.
Answer: 10⁻⁸°⁹
<u>Step-by-step explanation:</u>
![pH=log\bigg(\dfrac{1}{[H^+]}\bigg)\\\\\text{use log expansion rules to get:}\\pH=log\ 1-log\ [H^+]\\\\8.9=0\ -\ log\ [H^+]\\\\8.9=-log\ [H^+]\\\\-8.9=log\ [H^+]\\\\\text{use log transformation rules to get the following exponential equation:}\\10^{-8.9}=[H^+]](https://tex.z-dn.net/?f=pH%3Dlog%5Cbigg%28%5Cdfrac%7B1%7D%7B%5BH%5E%2B%5D%7D%5Cbigg%29%5C%5C%5C%5C%5Ctext%7Buse%20log%20expansion%20rules%20to%20get%3A%7D%5C%5CpH%3Dlog%5C%201-log%5C%20%5BH%5E%2B%5D%5C%5C%5C%5C8.9%3D0%5C%20-%5C%20log%5C%20%5BH%5E%2B%5D%5C%5C%5C%5C8.9%3D-log%5C%20%5BH%5E%2B%5D%5C%5C%5C%5C-8.9%3Dlog%5C%20%5BH%5E%2B%5D%5C%5C%5C%5C%5Ctext%7Buse%20log%20transformation%20rules%20to%20get%20the%20following%20exponential%20equation%3A%7D%5C%5C10%5E%7B-8.9%7D%3D%5BH%5E%2B%5D)
Ok so we have the first portion. We need to do cross multiplication first. So that would be 20(2x - 9) and 10(9)
So
20(2x - 9)=90
40x - 180=90
Then add 180 to itself then to 90
40x=270
X=6.75
Now let’s set the next one up knowing what we know from the previous one.
18(3x + 4)= 12(15)
54x + 72=180
Subtract 72 from it’s self and 180
54x=108
X=2
Answer:
9.85
Step-by-step explanation:


= 9.8488
<em>good luck, i hope this helps :)</em>