Answer:
a.
![S = 3 + 5t](https://img.qammunity.org/2021/formulas/mathematics/high-school/ktmz0jbc5ycwjpihunrg4m7fed7rqgukqf.png)
b.
![S = 18\ miles\ from\ the\ bank](https://img.qammunity.org/2021/formulas/mathematics/high-school/3atvdebiarqyic7gswrzqkaitzmy66np28.png)
c. Graph in the image attached
Explanation:
a.
We can model how far from the bank Mr Reder is using a linear equation:
![S = So + v*t](https://img.qammunity.org/2021/formulas/mathematics/high-school/k40nzsnt1t5wo6r9oz88rfjnfjir4zpvla.png)
Where S is his final position, So is his inicial position, v is his velocity and t is the time elapsed.
So, if we have So = 3 miles and v = 5 miles per hour, we have:
![S = 3 + 5t](https://img.qammunity.org/2021/formulas/mathematics/high-school/ktmz0jbc5ycwjpihunrg4m7fed7rqgukqf.png)
b.
To find his position after 3 hours, we just need to use t = 3 and then find the value of S:
![S = 3 + 5*3](https://img.qammunity.org/2021/formulas/mathematics/high-school/i5c3mh4sm6b3fzfj60gfrfhxqdjlq3vhtw.png)
![S = 3 + 15 = 18\ miles\ from\ the\ bank](https://img.qammunity.org/2021/formulas/mathematics/high-school/zi636hjhyneiircc956qswrikj6u6sctos.png)
c.
The graph of the equation is in the image attached.