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).
Answer:
0.67
Step-by-step explanation: From Delta math
Answer:
yes
Step-by-step explanation:
25x² - 40xy + 16y² can be factored as
(5x - 4y)² ← a perfect square
Answer:
add 12 +9 because i had that same answer on my quiz last week
Answer:
4-c/3 is ans
Step-by-step explanation:
3x+c=4
3x=4-c
x=4-c/3