若等腰三角形的周长为12,则腰长a的取值范围是 _________ .
3<a<6
汉译英:“集装袋;塑料袋;塑编袋”,正确的翻译为()。
A.jumbo bag;plastic woven bag;plastic bag
B.jumbo bag;plastic bag;plastic woven bag
C.plastic bag;jumbo bag;plastic woven bag
D.plastic woven bag;plastic bag;jumbo bag
电动机两相运行时,电流表指示()
A.变大
B.变小
C.为零
D.变大或为零