14 is the answer sorry if I get it wrong :/
Answer:
The critical value that should be used in constructing the confidence interval is T = 1.316.
The 80% confidence interval for the mean waste recycled per person per day for the population of Montana is between 2.741 pounds and 2.859 pounds.
Step-by-step explanation:
We have the standard deviation for the sample, which means that the t-distribution is used to solve this question.
The first step to solve this problem is finding how many degrees of freedom, we have. This is the sample size subtracted by 1. So
df = 26 - 1 = 25
80% confidence interval
Now, we have to find a value of T, which is found looking at the t table, with 25 degrees of freedom(y-axis) and a confidence level of
. So we have T = 1.316
The critical value that should be used in constructing the confidence interval is T = 1.316.
The margin of error is:

In which s is the standard deviation of the sample and n is the size of the sample.
The lower end of the interval is the sample mean subtracted by M. So it is 2.8 - 0.059 = 2.741 pounds
The upper end of the interval is the sample mean added to M. So it is 2.8 + 0.059 = 2.859 pounds.
The 80% confidence interval for the mean waste recycled per person per day for the population of Montana is between 2.741 pounds and 2.859 pounds.
Answer: 150 feet : 100 feet
Step-by-step explanation:
From the question, we are informed that the scale used by Eric was 1inch=5feet.
If the gym is 30 inches by 20 inches in the drawing, the acual length and width of the gym would be:
Length = 30 inches = 30 × 5 feet = 150 feet
Width = 20 inches = 20 × 5 feet = 100 feet
Therefore, the acual length and width of the gym would be 150 feet by 100 feet
When stone hits the ground, it's height will be zero, and since we're finding the time that's required for the stone to hit the ground, we can set h = 0 and solve for t.
Questions like this ("how much higher is x than y?") are answered by computing the ratio of the two quantities.
In fact, for example, the answer to "how much higher is 10 than 5?" is 2, because 10:5 = 2, and indeed 10 is twice as much as 5.
So, we have

So, the melting temperature of platinum is about one time and a half higher than the melting temperature of gold.