Letter F and 155° are supplements.
F = 180 -155 =25°
F = 25
E completes the angle with 90° and F.
E + 90 + 25 = 180
E = 180 - 115 = 65°
E = 65
G and 143° are supplements:
G + 143° = 180
G = 180 - 143 = 37°
G = 37
H completes the inner angles of a triangle with 44° and G:
H + 44° + 37° = 180°
H = 180 - 81 = 99°
I and H are supplements:
I + 99° = 180°
I = 180° - 99° = 81°
I = 81
R is opposite of a 90° angle:
R = 90°
T completes a triangle with 30° and 90 °
T + 30 + 90 = 180
T = 180 - 120 = 60°
T = 60
W and 168° are supplements:
W + 168° = 180°
W = 180° - 168° = 12°
W = 12
Y completes the triangle with 89° and W:
Y + 89° + 12°= 180°
Y = 180° - 111° = 69°
Y = 69