Answer:
The 80% confidence interval for the the population mean nitrate concentration is (0.144, 0.186).
Critical value t=1.318
Step-by-step explanation:
We have to calculate a 80% confidence interval for the mean.
The population standard deviation is not known, so we have to estimate it from the sample standard deviation and use a t-students distribution to calculate the critical value.
The sample mean is M=0.165.
The sample size is N=25.
When σ is not known, s divided by the square root of N is used as an estimate of σM:

The degrees of freedom for this sample size are:

The t-value for a 80% confidence interval and 24 degrees of freedom is t=1.318.
The margin of error (MOE) can be calculated as:
Then, the lower and upper bounds of the confidence interval are:

The 80% confidence interval for the population mean nitrate concentration is (0.144, 0.186).
Circumference = 2×3.14×r
3.14 is pie and r is the radius.
To find the radius you divide the diameter by 2.
19 ÷ 2 = 9.5
2×3.14×9.5 = 59.66
Multiply 59.66 by 6 because ther are 6 pennies.
59.66 × 6 = 357.96 mm.
Answer:
There are currently 50 states in the United States.
The number of states in 1795 in the United States = 15
Now, the fraction of the states that had become a part of the United States by 1795 is given below:

Answer:
4,2
Step-by-step explanation:
Isosceles mean two sides are same
My Question:
Why were there so many people on this question?
Answer:
The solution is: (2, -1)
Step-by-step explanation:
First we rewrite the second system equation
→ 
Now we have the following system of equations:


To solve the system multiply the first equation by -3 and add it to the second equation


--------------------------------------


Now we substitute the value of y in the first equation and solve for x



The solution is: (2, -1)