C. 0.0031
6.2 divided by 2,000 = 0.0031
First, we need to know the smallest two digit prime number. It can't start with one, since one is not prime, so it must start with two (or be in the twenties.) 20 is divisible by 2, 4, 5, and 10, 21 is divisible by 7 and 3, 22 is divisible by 2 and 11, so the smallest prime number is 23.
Now we need the largest two-digit prime number. It cannot start with nine or eight, since both are composite, so it must start with seven (be in the seventies.) 79 is the largest integer in the seventies and also happens to be prime, so there's our largest two digit prime number.
now we just need to add them for the sum:
23+79=102
hope I helped, and let me know if you have any questions :D
Um.. Both of those equations are the exact same. Divide both sides of the first equation by 6. You get:

That is the exact same as the second equation. This system has an infinite number of solutions. 5x - 7y = -1 is a line, so basically every point on that line is a solution to the system.
For example,

and

would work, but so would

and
2,3,4,1, the probability is in order from greatest to least. If they asked for least to greatest then, 1,4,3,2. So use the least to greatest one.