20 Answer: a₁ = 4
<u>Step-by-step explanation:</u>

21 Answer: n = 13
<u>Step-by-step explanation:</u>

22 Answer: n = 5
<u>Step-by-step explanation:</u>

Answer: D
H0: μ=522
H1: μ>522
Step-by-step explanation:
The null hypothesis (H0) tries to show that no significant variation exists between variables or that a single variable is no different than its mean. While an alternative Hypothesis (Ha) attempt to prove that a new theory is true rather than the old one. That a variable is significantly different from the mean.
So, for this case;
The null hypothesis is that the mean score equals to 522
H0: μ=522
The alternative hypothesis is that the mean score is greater than 522.
H1: μ>522
Answer:
X=34°
Y= 56°
Angle HIF are 90° when we bisectors YI 90-34
Therfore y = 56°
FGI are a triangle sum of it is 180 = 90+56
146 - 180
X= 34
Answer:
the answer is negative infinity to infinity since the range is -66 to infinity