下列关于扶壁式挡土墙的构造的叙述，正确的是（）。 A.两扶壁之间的距离宜取挡墙高度的

人们每天通过摄取食物不断补充所需要的各种元素，但有时也会摄入某些有害的元素。请指出下列矿物元素中，哪些是人体必需的微量元素，哪此进对人体有害的微量元素。（试用线连接）

正常8岁儿童腕部骨化中心数目为（）。

A.9

B.8

C.7

D.10

E.6

如果工程延期竣工，承包人有义务保证履约担保继续有效。由于发包人原因导致延期的，继续提供履约担保所需的费用由（）承担；由于承包人原因导致延期的，继续提供履约担保所需费用由（）承担。

A.承包人，承包人

B.发包人，发包人

C.承包人，发包人

D.发包人，承包人

Questions 9-13

·You will hear five people talking about "Whether They Write for Themselves or for Their Readers ".
·For questions 9 to 13, choose from the list A to F what each speaker says.
·Use the letters only once. There is one extra letters which you do not need to use.

• A. It all depends on the type of writing.
• B. I always write for myself and never care about the readers.
• C. I definitely write for myself but I try not to cause unnecessary offences.
• D. I actually write both for myself and for my readers.
• E. I have no idea at all for whom I write.
• F. I write mostly for myself and hope for any readership.
  Speaker 1 (/9 )
  Speaker 2 (/10 )
  Speaker 3 (/11 )
  Speaker 4 (/12 )
  Speaker 5 (/13 )

梯形结（猪蹄扣）它的特点是易结易解，便于使用，常用来抬较重的物体时用。（）