植物体的一个果实中含有种子的多少取决于_________的多少 [ ]
A.一朵花中雌蕊的数目
B.一朵花中雄蕊的数目
C.一枚雌蕊中子房的数目
D.一个子房中胚珠的数目
答案:D
砖墙上有1.2m宽门洞,门洞上设有钢筋混凝土过梁,若过梁上墙高为1.5m,则计算过梁上墙重时,应取墙高为( )。
A.(A) 0.4m
B.(B) 0.5m
C.(C) 0.6m
D.(D) 1.5m
As they access the corporate network, mobile and remote users inadvertently can infect the network with ______ and worms acquired from unprotected public networks.
A.sickness B.disease C.germs D.viruses