Answer:
A) x-8
Step-by-step explanation:

because

Answer: The y-intercept would be 10
Step-by-step explanation:
(-2, 15), (1, 6), (2, 3), (4, -3), (7, -12) are the coordinate points, you can graph it to find the intercept. I used the graphing calculator desmos.
The sample which is likely to produce the most valid result is Richard's sample because there was no statistical bias. Statistical bias is the systematic favoritism of certain individuals in the study. Just like what Adriana, Henry and Malik did in conducting their surveys, they choose people who are point of interest and also who are near them. In the way Richard conducted his survey, he used a random sampling technique, this is a method of selecting a sample from a population in such a way that every possible individual can be chosen and he doesn't know who these people are.
Divide each by 100. You get the ratio
765 : 1000
Now divide by 5
153 : 200
You can use this or
0.765 : 1