Answer:
The claim that the scores of UT students are less than the US average is wrong
Step-by-step explanation:
Given : Sample size = 64
Standard deviation = 112
Mean = 505
Average score = 477
To Find : Test the claim that the scores of UT students are less than the US average at the 0.05 level of significance.
Solution:
Sample size = 64
n > 30
So we will use z test

Formula : 


Refer the z table for p value
p value = 0.9772
α=0.05
p value > α
So, we accept the null hypothesis
Hence The claim that the scores of UT students are less than the US average is wrong
Answer: (-3,4) and (9,20)
I think these two points will make the answer you have been looking for.
C = 10m + 30, where C is total cost and m is # of months
C = 10(5) + 30
C = 50 + 30
C = $80
$160 = 10m + 30
160 - 30 = 10m
130/10 = m
m = 13 months
Hope that helps