Answer:
Kindly check explanation
Step-by-step explanation:
The alpha level set at the beginning of of an experiment is used by the researcher to the limit the probability if making a type 1 error. The type 1 error is committed when a true null hypothesis is incorrectly rejected.
The type 2 error on the other hand is committed when fail to reject a false null hypothesis.
Hence, in other to forestall the risk of incorrectly rejecting a true null hypothesis, the alpha level is set.
When critical region is split across both tails of the distribution, The z-score boundaries at an alpha level α = .05
α = .05 (95% confidence level)
When region is split into 2:
α/2 = .05/2
α/2 = 0.025
Loooking up the z table for the Zscore with probability of 0.025
Zscore = ±1.96
Answer:
SD = 7588.09
Step-by-step explanation:
Check the distribution table attached to for the step by step solution:
The formula for the mean, 

The variance , 

Standard Deviation,

SD = 7588.09
<u>Given</u>:
Given that the regular decagon has sides that are 8 cm long.
We need to determine the area of the regular decagon.
<u>Area of the regular decagon:</u>
The area of the regular decagon can be determined using the formula,

where s is the length of the side and n is the number of sides.
Substituting s = 8 and n = 10, we get;

Simplifying, we get;




Rounding off to the nearest whole number, we get;

Thus, the area of the regular decagon is 642 cm²
Hence, Option B is the correct answer.
If every 5 mins, A makes 1 yo-yo every 10 mins, B makes 1 yo-yo then every 10 mins, both machines produce 3 yo-yos every 10 mins (2 from machine A and 1 from machine B) Therefore, for 20 yo-yos, both machines would take 70 minutes( 1 hour and 10 mins). After 70 minutes, 21 yo-yos would be produced.