Answer:
The critical value of <em>t</em> at 0.01 level of significance is 2.66.
Step-by-step explanation:
The hypothesis for the two-tailed population mean can be defined as:
<em>H₀</em>: <em>μ </em>= <em>μ₀</em> vs. <em>H₀</em>: <em>μ </em>≠ <em>μ₀</em>
It is provided that the population standard deviation is not known.
Since there is no information about the population standard deviation, we will use a <em>t</em>-test for single mean.
The test statistic is defined as follows:

The information given is:
<em>n</em> = 55
<em>α</em> =<em> </em>0.01
Compute the critical value of <em>t</em> as follows:

*Use a <em>t</em>-table for the value.
If the desired degrees of freedom are not provided consider he next highest degree of freedom.
Thus, the critical value of <em>t</em> at 0.01 level of significance is 2.66.
Answer:

Step-by-step explanation:
Use the square of a binomial theorem
= 
Now expand the given equation:

Hope this helps :)
Have a great day!
Answer:
YES
Step-by-step explanation:
because they are all different lengths