Answer/Step-by-step explanation:
a. The sides of ∆ABC can be labelled as follows, taking θ as the reference point.
Adjacent = side AB
Opposite = side BC
Hypotenuse = side AC
b. I. "<B is an acute angle" => FALSE. It is a right angle (90°)
II. "The side opposite to <C is BC" => FALSE. The side opposite to <C is AB.
III. The side adjacent to <A is AB => TRUE
IV. The side opposite to <B is not the longest. => FALSE. It is the hypotenuse and the longest side.
c. Cos θ =
![(adjacent)/(hypotenuse) = (AB)/(AC)](https://img.qammunity.org/2021/formulas/mathematics/high-school/mc32bwg0a5r26m3mnho2uc32pyk7gypsq1.png)
Tan θ =
![(opposite)/(adjacent) = (BC)/(AB)](https://img.qammunity.org/2021/formulas/mathematics/high-school/1z1x9pwg2cbfgqonvmjfhj945pq3t1hsfd.png)
d. Sin C =
![(opp)/(hypo) = (AB)/(AC)](https://img.qammunity.org/2021/formulas/mathematics/high-school/3qqc2x20xkzetg6kmqvzqp56b1hfyad7f9.png)
Cos C =
![(adjacent)/(hypotenuse) = (BC)/(AC)](https://img.qammunity.org/2021/formulas/mathematics/high-school/ft3pedwxuu5e2ydxf3amcx96cymfc36cv0.png)
Tan C =
![(opp)/(adjacent) = (AB)/(BC)](https://img.qammunity.org/2021/formulas/mathematics/high-school/bokgtvq73bfhapjsydfk6erehd5cj1o63k.png)