Answer:
A.) f(x) = 45 - 4(x - 1)
Step-by-step explanation:
Considering the situation described, we have that:
- The appropriate null hypotheses is
.
- The appropriate alternative hypotheses is
.
<h3>What are the hypotheses tested?</h3>
At the null hypotheses, it is tested if the mean has not been reduced, that is, it still is of 5.2 hours, hence:
.
At the alternative hypothesis, it is tested if the mean has been reduced, that is, it is now of less than 5.2 hours, hence:

More can be learned about hypotheses tests at brainly.com/question/26454209
The probability that Boris will win the contest is:
P = 0.286
<h3>
How to get the probability?</h3>
For some given odds a:b, the probability is just computed as the quotient between a and b, which gives:
P = a/b
In this case, the odds are 2:7, so the probability that Boris will win the contest is:
P = 2/7 = 0.286
Written in percentage form, we get:
P = 28.6%
If you want to learn more about probability:
brainly.com/question/24756209
#SPJ1
6 weeks × 20 dollars = $120