tolong ya ok ........

L Persegi Panjang = p x l

1 lingkaran = d = 2r = 2 x 3,5 cm = 7 cm
panjang persegi panjang = 5 diameter lingkaran = 5 x 7 cm = 35 cm
lebar persegi panjang = 4 diamter lingkaran = 4 x 7 = 28 cm

V balok = p x l x t = 35 cm x 28cm x10 = 9800 cm³

Luas lingkaran = [tex] \pi r^{2} [/tex] atau [tex] \frac{1}{4} \pi d^{2} [/tex]
Luas Lingkaran = [tex] \frac{1}{4} [tex] \frac{22}{7} [/tex] 7^{2} [/tex]
Luas lingkaran = 38,5 cm²

20 Luas lingkaran = 20 x 38,5 cm² = 770 cm²

Volume lingkaran = Luas Lingkaran x t = 770 cm² x 10 cm = 7700 cm³

The volume of the space is 9800cm³-7700cm³ = 2100 cm³
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hope  u understand it ^^