Not sure at di ko masyado magets yung instructions kasi sabog ako pero...
Step-by-step explanation:
We will be using the formula:
S=(n-2)×180°
1) (6-2)×180°
=4×180°
=720°
2) (8-2)×180°
=6×180°
=1080°
3) (12-2)×180°
=10×180°
=1800°
4) (13-2)×180°
=11×180°
=1980°
5) (18-2)×180°
=16×180°
=2880°
Hope it helps.