Answer: B. between 7 and 10 ft
Explanation: To find the length of \( AB \) in \(\triangle ABC\), we can use the Law of Cosines. This theorem relates the lengths of the sides of a triangle to the cosine of one of its angles. Given the sides \( AC = 10 \) ft, \( BC = 7 \) ft, and angle \( C = 68^\circ \), we can find \( AB \).
Steps:
- Law of Cosines Formula:
where \( c \) is the side opposite angle \( C \).
- Substitute the Known Values:
- Calculate:
- Find \(\cos(68^\circ)\):
- Continue Calculation:
- Solve for \( AB \):
Since \( AB \approx 9.82 \) ft, it falls between 7 and 10 ft. Thus, the correct answer is B. between 7 and 10 ft.