See attached picture for solution:
Using the z-distribution, it is found that the lower bound of the 99% confidence interval is given by:
d. 68.39%.
<h3>What is a confidence interval of proportions?</h3>
A confidence interval of proportions is given by:

In which:
is the sample proportion.
In this problem, we have a 99% confidence level, hence
, z is the value of Z that has a p-value of
, so the critical value is z = 2.575.
The sample size and estimate are given by:

Hence, the lower bound is given by:

Hence the lower bound is of 68.39%, which means that option D is correct.
More can be learned about the z-distribution at brainly.com/question/25890103
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Answer:
4.8
Step-by-step explanation:
15/6 is 2.5 whitch when divided by 12 is 4.8 so 12 divided by 2.5 is 4.8
Newton's law of cooling says the rate of change of temperature is proportional to the difference between the object's temperature and the temperature of the environment.
Here, the object starts out at 200 °F, which is 133 °F greater than the environment temperature. 10 minutes later, the object is 195 °F, so is 128 °F greater than the environment. In other words, the temperature difference has decayed by a factor of 128/133 in 10 minutes.
The solution to the differential equation described by Newton's Law of Cooling can be written as the equation
T(t) = 67 + 133*(128/133)^(t/10)
where T is the object's temperature in °F and t is the time in minutes from when the object was placed in the 67 °F environment.
The equation
T(t) = 180
can be solved analytically, but it can be a bit easier to solve it graphically. A graphing calculator shows it takes
42.528 minutes for the temperature of the coffee to reach 180 °F.