温度应力裂缝产生的主要原因是（）。 ["混凝土塌落度大","浇筑完没有及时覆盖","混凝土内外温差较大","施工工艺不正确"]
Given： 10. class One { 11. void foo（） { } 12. } 13. class Two extends One { 14. //insert method here 15. } Which three methods， inserted individually at line 14， will correctly complete class Two？（） [" public void foo（） { \/* more code here *\/ }"," private void foo（） { \/* more code here *\/ }"," protected void foo（） { \/* more code here *\/ }"," int foo（） { \/* more code here *\/ } "," void foo（） { \/* more code here *\/ }"]
多级离心泵的压头等于（），而流量等于（）。
Which three statements are true regarding persistent lightweight jobs？（） [" Persistent lightweight jobs modify several tables in the data dictionary to generate a lot of redo."," The user cannot set privileges on persistent lightweight jobs."," Persistent lightweight jobs are useful when users need to create a large number of jobs in a short time."," Persistent lightweight jobs are useful when users need to create a small number of jobs that run infrequently."," The use of a template is mandatory to create persistent lightweight jobs."]
在选用刀具材料时，在保持足够的强度和韧性的条件下，应尽可能有高的（） ["硬度","耐热性","硬度和耐热性","硬度和耐磨性"]
举例说明鱼类鳞片的主要类型。
