The solutions are basically the points on the graph that the line passes through. The best way to pick them is to use the whole numbers that are on the corners of the little boxes instead of the middle.
(4, -5)
(3, -3)
(1, 1)
(0, 3)
(-1, 5)
and so on.
1) A. Biased because the population could be uneven. Too many of one ethnicity, too many of one gender, etc.
2) I believe this one is C. because there are not enough people. You need to survey the majority of parents instead of a selected few.
3) There are 80 green marbles per 500, therefore calculate the percentage.

or

percent. Multiply

percent or

times 25. It gives you

.
4) This one is a probability thing too. For every 500 batteries, there are 3 that are defective, therefore,

.

5) Yet another one. Add up all the nuts and you get

. The chance of getting a cashew from these

is:

.
Therefore:
So base on the question, that states the weight of Rex from last year to the present, and find its rate if change or percentage of change. To calculate the percentage you must first subtract the said weight in the present to its past then divide it by its past weight then multiply it by 100. So the percentage would be 15 %. I hope this would help