How to do this question plz answer me step by step plzz plz

Answer:
[tex] \boxed{\sf Perimeter \ of \ semicircle = 3 \pi \ cm} [/tex]
Given:
Radius of semicircle (r) = 3 cm
Step-by-step explanation:
[tex]\sf Perimeter \ of \ semicircle = \pi r [/tex]
[tex] \sf = 3 \pi \: cm[/tex]