Tolong nmr 6,7,8 yah

6) C. 1 017 , 36

cara :
d = 18 cm --> r = 9 cm
s = 15 cm

t² = s² - r²
= 15² - 9²
= 225 - 81
= 144
t = √ 144
= 12

V = 1/3 . 3,14 . r² . t
= 1/3 . 3,14 . 81 . 12
= 1017 , 36 cm³