Answer Happy

(a) If 𝜃 is in standard position, then the reference
angle 𝜃 is the acute angle formed by the terminal
side of 𝜃 and the (?) . So the reference angle
for 𝜃 = 110° is 𝜃 = (?) ° , and
that for 𝜃 = 210° is 𝜃 = (?)
°.
(b) If 𝜃 is any angle, the value of a trigonometric
function of 𝜃 is the same, except possibly for sign, as
the value of the trigonometric function
of 𝜃. So sin(110°) = sin
(?°), and sin(210°) = −sin (?°)