Answer:
d. The population standard deviation is known.
Step-by-step explanation:
T-distribution or Z-distribution, which to use?
If we have the population standard deviation is known, we use the z-distribution.
Otherwise, if we only have the standard deviation for the sample, we use the t-distribution.
Which of the following is not appropriate to use the t-confidence interval for
When the population standard deviation is known, so letter d.
So it gives you the diameter but you need the radius of the circle to find the area so to find the radius you just divide the diameter by two. the formula for the area of a circle is A=pi*r^2 so you just multiply 3.14 by 3 squared so you just put it in the calculator as A=3.14*3^2 and you get 28.26 hope this helped
Answer:
130°
Step-by-step explanation:
180-50=130°
