It’s 39. You got it right
Please comment the question which goes with the picture so I can try to help.
<span>The reference angle is closest to the x-axis.
I will assume the above is 7pi/6. That would be a reference angle of pi/6, and the sin in the 3rd quadrant is negative, so the sin theta = - 0.5</span>
5.4 because you set up a proportion 7/19=2/x, 19*2=38, 38/7=5.4285, rounded you get 5.4
2 6/7 ÷ 2/3
= 20/7 ÷ 2/3
20/7 × 3/2
= 60/14
reduce to it's lowest term
30/7 = 4 2/7