A.5 B.10 C.15 D.20
A.30 B.10 C.20 D.40
A.窗臺(tái)無(wú)積塵 B.墻壁無(wú)蛛網(wǎng) C.墻壁屋頂無(wú)積塵、蛛網(wǎng) D.墻壁無(wú)積塵