If the recipe makes enough stew for 6 people, and the ingredients cost $9.75, then for 24 people it will cost $x. You can write this statement as
6 people - $9.75,
24 people - $x.
Or as proportion,

Find x:

Answer: It would cost $39 to serve 24 people
Answer: See description below.
The residuals are the differences between the predicted values and the actual values. You will need to make a scatter plot of each difference.
Here are the five points that you will need to plot:
20 - 21 = -1 (1, -1)
17 - 16 = 1 (2, 1)
9 - 10 = -1 (4, -1)
6 - 5 = 1 (5, 1)
2 - 2 = 0 (6, 0)
Divide distance with time
Question 3:
If the diver is being pulled up at 25 feet every minute, in 10 minutes they would have been pulled up 10 times that
10*25=250
The diver is now 200 feet below, but 10 minutes ago they would have been 250 feet deeper so:
200+250=450
450 feet