Answer: 6
Step-by-step explanation:
Slope is found by doing:

(x1 and y1 must be from the same ordered pair and x and y must be from the same ordered pair, however point (x1,y1) and (x,y) can be used interchangeably)
Let us say that (x1,y1) is (3,18)
And (x,y) is (5,30)

Step-by-step explanation:
vv
Can be expressed as y=0.55n
1-2. The best estimate for the population mean would be sample mean of 60 gallons. Since we know that the sample mean is the best point of estimate. Since sample size n=16 is less than 25, we use the t distribution. Assume population from normal distribution.
3. Given a=0.1, the t (0.05, df = n – 1 = 15)=1.75
4. xbar ± t*s/vn = 60 ± 1.75*20/4 = ( 51.25, 68.75)
5. Since the interval include 63, it is reasonable.
Answer:
4
Step-by-step explanation: