不等式x+x3≥0的解集是______．

请阅读下面短文，根据短文内容从每小题所给的A、B、C、D四个选项中选出最佳选项，并在答题卷上将该项涂黑。（每小题2分）

小题1:How much are the musical tickets for two children?

A. 16 pounds,         B, 35 pounds.        C. 30 pounds.        D. 40 pounds.

小题2:When will the Teenage Drawing Competition be held?

A．On June 7th.

B．On August 6th.

C．On September 20th.

D．On April 25th.小题3:Where can you watch Adele's performance this Sunday afternoon?

A．At St. James' s Park.

B．At Westfield Theater.

C．At Westfield Shopping Center.

D．At Cambridge Theater.

正常龈沟探诊深度是（）

A.≤0.5mm

B.≤lmm

C.≤2mm

D.2~3mm

E.≤3mm

压疮：

某矿品位为0.4，精矿品位为8，尾矿品位为0.05，其回收率为（）。

A．80%

B．20%

C．88%

封顶