A:由圆的性质可推出球的有关性质
B:由等边三角形、等腰直角三角形的内角和是 180° ,归纳出所有三角形的内角和都是 180°
C:某次考试小明的数学成绩是满分,由此推出其它各科的成绩都是满分
D:金属能导电,金、银、铜是金属,所以金、银、铜能导电
It's 3:30 p. m. Kangkang and his classmates are busy _____ basketball on the playground.