Answer:
<h2>3 g/cm³</h2>
Step-by-step explanation:
The density of a substance can be found by using the formula

From the question we have

We have the final answer as
<h3>3 g/cm³</h3>
Hope this helps you
Note :- If sample size n > 30 OR Population standard deviation σ is given then We use Z test.
If sample size n < 30 AND Population standard deviation σ is unknown then we use t test.
In this question we are not given Population standard deviations σ1 and σ2.
Also n1 = 14 and n2 = 13 both sample sizes are LESS than 30.
Therefore we use t test.
Given :- Assume the population standard deviations are equal. ( σ1 = σ2)
then Degrees of freedom = n1 + n2 - 2 = 14 + 13 - 2 = 25.
(kindly find the image attached with this solution)
Answer :- Therefore 25 degrees of freedom are used to find the t critical value.
<h2>A)</h2>


<h2>B)</h2><h3>Since we only have 75 tickets to sell, the domain is:</h3><h2>t ε [ 0 , 75 ]</h2>
<h2>Range: (extra)</h2><h2>m ε [ 0 , 225 ] </h2>
well, let's split the hours in minutes, so since 1 hr is 60 minutes, so he can walk 2.833 miles in 60 minutes, well, 3 hrs is 3*60 = 180 minutes, then we add 15 minutes, that's 195 minutes.
if he can walk 2.833 miles in 60 minutes, how long will it be for 195 minutes?
