1、单选题：
With carbon equivalent ( ), the steel has a low tendency to harden and cold cracking?
选项：
A:less than 0.40%
B:less than 0.60%
C:less than 0.50%
D:less than 0.80%
答案: 【less than 0.40%】

2、单选题：
( ) is not a factor that affects weldability.
选项：
A:Welding process
B:joint type
C:chemical composition
D:operation skill
答案: 【operation skill】

3、多选题：
The calculation formula of carbon equivalent of the IWS considers the influence of () on weldability.
选项：
A:welding structure&nbsp
B:diffusion hydrogen
C:welding process
D:chemical composition
答案: 【welding structure
diffusion hydrogen;
welding process】

4、单选题：
Maximum crack distance has been used to allow more accurate determination of the cracking ( ) range.
选项：
A:size
B:temperature
C:toughness
D:strength
答案: 【temperature】

5、多选题：
Weldability is not easily quantified, and can depend on a variety of factors, including ( ).
选项：
A:welding method
B:operator and welder
C:physical specifics of the joint
D:welded structure
答案: 【welding method;
physical specifics of the joint;
welded structure】