Tolong ya beserta penjelasannya :)

d = 21 cm

Keliling 1/2 lingkaran
= 1/2 x π x d
= 1/2 x22/7 x 21
= 1/2 x 22 x 3
= 1/2 x 66 cm
= 33 cm

Keliling bangun
= 33 cm + 25 cm + 25 cm
= 33 + 50
= 83 cm

25+25+K.1/2Lingkaran
=50+(1x22x21÷2÷7)
50+33
= 83 cm