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:
A = 7,241.2454026112 square mm.
or exact : A = 2,304.96*π sq mm
Step-by-step explanation:
Cylinder formula: A = π* r^2 + 2 *π * r* h + π*r^2
is the surface area.
d = 2r = 39.2 mm
h = 39.2 mm
r = 19.6 mm
A = π* r^2 + 2 *π * r* h + π*r^2
A = 2* π* (19.6)^2 + 2π (19.6)*(39.2)
A = 2,413.748467537 + 4,827.496935
A = 7,241.2454026112 square mm.
or
A = 2*pi* (768.32 + 384.16)
A = 2*1,152.48* pi
A = 2,304.96*π sq mm
Answer:
First part: -10x-4y=-12
Second half: infinitely many solutions
Step-by-step explanation:
Just did the assignment and got it correct
Answer:
0.13
Step-by-step explanation:
cos P = adj/hyp
cos P = 2/16
cos P = 1/8 = 0.125
cos P = 0.13
Answer:
41.6 lol
Step-by-step explanation: