42km = 26.098 miles. Hope this helps.
Just be honest with them and everything will work out :)
Hi there!
a.
To find the total amount of people that have ENTERED by t = 20, we must take the integral of the appropriate function.

Evaluate using a calculator:

b.
To solve, we can find the total amount of people that have entered of the interval and subtract the total amount of people that have left from this value.
In other terms:

We can evaluate using a calculator (math-9 on T1-84):


c.
If:

Then:

Evaluate at t = 20:


This means that at t = 20, there is a <u>NET DECREASE</u> of people at the movie theater of around 20.823 (21) people per hour.
d.
To find the maximum, we must use the first-derivative test.
Set S(t) - R(t) equal to 0:

Graph the function with a graphing calculator and set the function equal to y = 0:
According to the graph, the graph of the first derivative changes from POSITIVE to NEGATIVE at t ≈ 17.78 hours, so there is a MAXIMUM at this value.
<u>Thus, at t = 17.78 hours, the amount of people at the movie theater is a MAXIMUM.</u>
True. How do you apply information from the book into the tests? Books don't give the answers merely provide a foundation you must build upon.
Http://www.google.com/url?q=http://www.sosmath.com/algebra/inequalities/ineq01/ineq01.html&sa=U&ved=0ahUKEwjXwL6qvsnRAhUIdiYKHU8sDdkQFggPMAA&sig2=wLL4VtnQtN-9CevOb4M7Qw&usg=AFQjCNGIZD-7guk9urORDLjgMCHb1LqHJg