Not really Specific in asking in what way you want it answered... So here is what Im able to understand.
Function
Joseph : 20 + .23x = y
Micki : 10 + .15x =y
Hope this is what your asking...
A counter-example could be
There are more than 3 marbles in the bag, and the other ones are red.
Hope this helps!
Answer:
1) 
2) ![\sqrt[3]{y^5}=y^{\frac{5}{3}](https://tex.z-dn.net/?f=%5Csqrt%5B3%5D%7By%5E5%7D%3Dy%5E%7B%5Cfrac%7B5%7D%7B3%7D)
3) ![\sqrt[5]{a^{12}}=a^{\frac{12}{5} }](https://tex.z-dn.net/?f=%5Csqrt%5B5%5D%7Ba%5E%7B12%7D%7D%3Da%5E%7B%5Cfrac%7B12%7D%7B5%7D%20%7D)
4) ![\sqrt[4]{z^{9}}=z^\frac{9}{4}](https://tex.z-dn.net/?f=%5Csqrt%5B4%5D%7Bz%5E%7B9%7D%7D%3Dz%5E%5Cfrac%7B9%7D%7B4%7D)
Step-by-step explanation:
1) 
We know that 
So, 
2) ![\sqrt[3]{y^5}](https://tex.z-dn.net/?f=%5Csqrt%5B3%5D%7By%5E5%7D)
We know that ![\sqrt[3]{x}=x^{\frac{1}{3}](https://tex.z-dn.net/?f=%5Csqrt%5B3%5D%7Bx%7D%3Dx%5E%7B%5Cfrac%7B1%7D%7B3%7D)
So, ![\sqrt[3]{y^5}=y^{\frac{5}{3}](https://tex.z-dn.net/?f=%5Csqrt%5B3%5D%7By%5E5%7D%3Dy%5E%7B%5Cfrac%7B5%7D%7B3%7D)
3) ![\sqrt[5]{a^{12}}](https://tex.z-dn.net/?f=%5Csqrt%5B5%5D%7Ba%5E%7B12%7D%7D)
We know that ![\sqrt[5]{x}=x^{\frac{1}{5}](https://tex.z-dn.net/?f=%5Csqrt%5B5%5D%7Bx%7D%3Dx%5E%7B%5Cfrac%7B1%7D%7B5%7D)
So, ![\sqrt[5]{a^{12}}=a^{\frac{12}{5} }](https://tex.z-dn.net/?f=%5Csqrt%5B5%5D%7Ba%5E%7B12%7D%7D%3Da%5E%7B%5Cfrac%7B12%7D%7B5%7D%20%7D)
4) ![\sqrt[4]{z^{9}}](https://tex.z-dn.net/?f=%5Csqrt%5B4%5D%7Bz%5E%7B9%7D%7D)
We know that ![\sqrt[4]{x}=x^{\frac{1}{4}](https://tex.z-dn.net/?f=%5Csqrt%5B4%5D%7Bx%7D%3Dx%5E%7B%5Cfrac%7B1%7D%7B4%7D)
So, ![\sqrt[4]{z^{9}}=z^\frac{9}{4}](https://tex.z-dn.net/?f=%5Csqrt%5B4%5D%7Bz%5E%7B9%7D%7D%3Dz%5E%5Cfrac%7B9%7D%7B4%7D)
Arthur must earn $53 in the next week