Jawab yaaa soalnya dibutuhin banget jawabannya,,,,

2.  Keliling lingkaran = 2 п r
                                 = 2 x 22/7 x 56
                                 = 352 cm²
3.Luas lingkaran = п r²
                           = 3, 14 x 10 x 10
                           = 3,14 x 100
                           = 314 cm ²
4. Dik : K lingkaran = 198 cm
  Dit : a jari-jari=....?
         b diameter =....?
jwb : a jari-jari
            K= 2пr
          198= 2 x 3,14 x r
          198=6,28 xr
          198/6,28= r
           31, 52866242038217 = r

         b diameter
diameter = 2 r
diameter = 2 x 31, 52866242038217
diameter = 63, 05732484076433

Maaf ya kalau salah/keliru
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