Answer: Option C.
Explanation:
1. Apply the Pythagorean Theorem to calculate AB:
![AB=\sqrt{BC^(2)+AC^(2)}\\AB=\sqrt{(7.50mi)^(2)+(11.43mi)^(2)}\\AB=13.7mi](https://img.qammunity.org/2020/formulas/mathematics/middle-school/wcksjt047mdggf26waquitr9h746va912t.png)
2. Now, you can calculate the angle ∠A as following:
![tan^(-1)(\alpha)=(opposite)/(adjacent)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/89wip4hmw74gxalitpw7vq0wgephplnz2o.png)
Where:
![opposite=7.50\\adjacent=11.43](https://img.qammunity.org/2020/formulas/mathematics/middle-school/t3qun3fjs6lo3qid811t9sw87agmetk3i7.png)
Then:
![tan^(-1)(A)=(7.50)/(11.43)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/w1a3q24bk5ugi7aprvp123d4tg7q5j3i88.png)
∠
°
3. The sum of the interior angles of a triangle is 180°. So, you can find the angle ∠B as following:
∠
°-∠A-∠C
∠
°-
°-
°=
°
4. Therefore, the answer is the option c.