There are multiple answers like 15 16 17 18 19 and also 20. Are the correct answers
Answer:
The null and alternative hypotheses are:


Under the null hypothesis, the test statistic is:

Where:
is the sample mean
is the sample standard deviation
is the sample size

Now, the right tailed t critical value at 0.05 significance level for df = n-1 = 10-1 = 9 is:

Since the t statistic is less than the t critical value at 0.05 significance level, therefore,we fail to reject the null hypothesis and conclude that there is not sufficient evidence to support the claim that the average phone bill has increased.
-x+4>-3x-4
+x +x
---------------------
4>-3x-4
+4 +4
----------------
8>-3x
/3 /3
----------------
8>2.7
x=2.7
Hope it helped!
Letter c because if u multiply 5•3 you get 15
The distance between two points (x₁,y1),(x₂,y₂) is d

For the given problem we have
<span>W(1,8),X(7,8),Y(4,5), and Z(1,2)
The length of WY = </span>

= 3√2
The length of WX =

= 6
The length of WZ =

= 6
The length of XY = <span><span>

= 3√2
</span>The length of ZY = </span><span>

= 3√2
∴ WX = WZ ⇒⇒⇒ proved
XY = ZY ⇒⇒⇒ proved
WY = WY ⇒⇒⇒ reflexive property
∴ Δ</span><span>WYZ is congruent to ΔWYX by SSS method</span>