画一个周长是6.28厘米的圆，并求出面积．并且用字母表示出半径、直径、圆心．
直接写得数． 12×= 6÷=÷= 1÷×=×18=×0×=×=×26=
直接写出得数．×60= 12÷= 3.14×42=（）2=×=+=÷=÷=
直接写得数．×4=+=+=÷= 25÷=﹣=÷5=×= 2÷=﹣=×12= 2﹣﹣=
口算========
直接写出得数．== 11=== 0÷1.2======= 12=== 54=
= 6÷
=
÷
= 1÷
×
=
×18=
×0×
=
×
=
×26=
×60= 12÷
= 3.14×42=（
）2=
×
=
+
=
÷
÷
=
×4=
+
=
+
=
÷
=
=
﹣
=
×
=
=
﹣
=
=
=
=
=
=
=
=
=
=
=
= 11
=
=
= 0÷1.2=
=
=
=
=
=
=
=
=
= 54
=
粤公网安备 44130202000953号