tolong di jawab pake cara ya!!

1.diameter lingkaran besar=42?
rb=½. 42=21
rk:rb=2:3
rk=⅔.21=14
L arsir=Lb-Lk
=½.22/7.21.21-½.22/7.14.14
=693-308
=385
No. 2
K=2.25+2.30+2.38
=50+60+76
=186
3.diameter kolam=14 m
r=½. 14=7
r pagar=7+3,5=10,5
K=2πr
=2.22/7.10,5
=66 m