bantubyaaaaaaaaaaaaaaaaa. no 29.sama 30

29.
V kubus 1 = s^3 = 15^3= 3375
V kubus 2 = s^3 = 18^3 = 5832
Jadi selisihnya 5832-3375 = 2457

30.
Lp tabung = 2pi.r (r+t) = 2.22/7.14 (14+25) = 88(39) = 3432