I only need number 18 and 19 please show work if you can

Step-by-step explanation:
Size of Exterior angle = 360°/n, where n represent the number of sides of the regular polygon.
Question 18:
Pentagon = 5 sides,
Exterior angle = 360°/5 = 72°.
Question 19:
Exterior angle = 360°/36 = 10°.