Answer:
C is the answer
Step-by-step explanation:
<h2><u>
Answer with explanation</u>
:</h2>
Let
be the average life of light bulbs.
As per given , we have
Null hypothesis : 
Alternative hypothesis : 
Since
is right-tailed and population standard deviation is also known, so we perform right-tailed z-test.
Formula for Test statistic : 
where, n= sample size
= sample mean
= Population mean
=population standard deviation
For
, we have

Using z-value table , Critical one-tailed test value for 0.06 significance level :

Decision : Since critical z value (1.5548) < test statistic (1.6180), so we reject the null hypothesis .
[We reject the null hypothesis when critical value is less than the test statistic value .]
Conclusion : We have enough evidence at 0.06 significance level to support the claim that the new filament yields a longer bulb life
The graph of the function is a parabola.
The nose comes down as far as y=4 but no farther.
That happens when (x - 2)² = 0 , and THAT happens when x = 2 .
Answer:
Both child tickets and senior tickets cost $14.
Step-by-step explanation:
Since the school that DeShawn goes to is selling tickets to the annual dance competition, and on the first day of ticket sales, the school sold 10 senior citizen tickets and 8 child tickets for a total of $ 252, while the school took in $ 280 on the second day by selling 10 senior citizen tickets and 10 child tickets, to determine what is the price of each of one senior citizen ticket and one child ticket, the following calculation must be performed:
10 senior tickets + 8 child tickets = 252
10 senior tickets + 10 child tickets = 280
280 - 252 = 2 child tickets
28 = 2 child tickets
28/2 = 1 child ticket
14 = 1 child ticket
14 x 10 = 140
(280 - 140) / 10 = senior tickets
140/10 = 14 = senior tickets
Therefore, both child tickets and senior tickets cost $14.