The last one. In arithmetic sequence, the difference between the terms is constant, in this case, the difference is 3
<span>16: 2r - 6 =22
2r = 22 + 6
2r = 28
r =28/2
r = 14
17: 3g + 7 = 31
3g = 31 - 7
3g = 24
g = 24/3
g= 8
18: 3f - 7 = 38
3f = 38 +7
3f = 45
f = 45/3
f = 15</span>
Angle 1=180-90-48 =42
Angle 2=180-42 =138
Angle 3= angle 1
Angle 4= angle 2
Angle 5 = 180-72-42=66