mohon dibantu jawabannya(no.2), terima kasih :)

a . tinggi kaleng
V = pi x r x r x t
785 = 3,14 x 5 x 5 x t
785 = 78,5t
t = 785/78,5
t= 10 cm
b. luas kaleng
L = 2 x pi x r ( r + t)
L = 2 x 3,14 x 5 ( 5 + 10)
L = 31,4 X 15
L =471 cm "

Volume silinder = (22/7) x r x r x t
diameter 10 cm, r = 5 cm

785 = (22/7) x 5 x 5 x t
t = 785/25 x (7/22)
t = 10 cm

Tinggi Kaleng = 10 cm

Luas Kaleng = Luas tutup + Luas alas + Luas badan kaleng

Luas tutup = Luas alas = (22/7) x 5 x 5 = 78,57 cm2
Luas badan = 2 x (22/7) x r x t = 44/7 x 5 x 10 = 314,29 cm2
Jadi luas kaleng = 78,57 + 78,57 + 314,29 = 471,13 cm2
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