一个周角=（ ）个平角=（ ）个直角
2；4
People pay more attention to protecting environment. There _________ less pollution in the future.
A．will have
B．will be
C．is going to have
D．are going to be
A．泡沫塑料的价格便宜
B．用泡沫塑料容易制作
C．泡沫塑料容易找到
D．泡沫塑料的密度较小
