Jawaban Penjelasan dengan langkah-langkah:

Luas Alas :

1. π x r² = x 28² = x 784 = 22 x 112 = 2464 cm²

2. π x r² = x 35² = x 1225 = 22 x 175 = 3850 cm²

3. π x r² = x 42² = x 1764 = 22 x 252 = 5544 cm²

4. π x r² = x 49² = x 2401 = 22 x 343 = 7546 cm²

5. π x r² = x 56² = x 3136 = 22 x 448 = 9856 cm²

Keliling alas :

1. 2 x π x r = 2 x   x 28 = 2 x  22 x 4 = 44 x 4 =  176 cm

2. 2 x π x r = 2 x   x 35 = 2 x  22 x 5 =  44 x 5 = 220 cm

3. 2 x π x r = 2 x   x 42 = 2 x  22 x 6 =  44 x 6 = 264 cm

4. 2 x π x r = 2 x   x 49 = 2 x  22 x 7 =  44 x 7 = 308 cm

5. 2 x π x r = 2 x   x 56 = 2 x  22 x 8 =  44 x 8 = 352 cm

Luas permukaan :

1. 2 x π x r x ( r + t ) = 2 x   x 28 x ( 28 + 7 ) = 2 x  22 x 4 x 35

= 44 x 140 =  6.160 cm²

2. 2 x π x r x ( r + t ) = 2 x   x 35 x ( 35 + 7 )  = 2 x  22 x 5 x 42

=  44 x 210 = 9.240 cm²

3. 2 x π x r x ( r + t ) = 2 x   x 42 x ( 42 + 7 )  = 2 x  22 x 6 x 49

=  44 x 294 = 12.936 cm²

4. 2 x π x r x ( r + t ) = 2 x   x 49 x ( 49 + 7 )  = 2 x  22 x 7 x 56

=  44 x 392 = 17.248 cm²

5. 2 x π x r x ( r + t ) = 2 x   x 56 x ( 56 + 7 )  = 2 x  22 x 8 x 64

=  44 x 512 = 22.528 cm²

Volume :

1. π x r² x t = x 28² x 7 = x 784 x 7 = 22 x 112 x 7

= 2.464 x 7 = 17.248 cm³

2. π x r² x t = x 35² x 7 = x 1.225 x 7 = 22 x 175 x 7

= 3.850 x 7 = 26.950 cm³

3. π x r² x t = x 42² x 7 = x 1.764 x 7 = 22 x 252 x 7

= 5.544 x 7 = 38.808 cm³

4. π x r² x t = x 49² x 7 = x 2.401 x 7 = 22 x 343 x 7

= 7.546 x 7 = 52.822 cm³

5. π x r² x t = x 56² x 7 = x 3.136 x 7 = 22 x 448 x 7

= 9.856 x 7 = 68.992 cm³