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Answer with explanation:</u></h2>
Let
be the population mean.
Null hypothesis : 
Alternative hypothesis : 
Since Alternative hypothesis is left tailed so , the test is a left tailed test.
Given : n=33 > 30 , so we use z-test.
Test statistic : 
i.e. 
Using z-value table,
P-value for left tailed test =
Since , the p-value (0.0020524) is less than the 0.05 level of significance, it means we reject the null hypothesis.
Therefore, we have enough evidence to support the claim that the mean completion time has decreased under new management.
Answer: there are 16 boys in the class which means not ever girl can have a bf
Step-by-step explanation:
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