管件的对口应内壁齐平，局部错口≯10％壁厚，且≯1mm。外壁差≯10％薄件厚度，且≯4mm。
参考答案：对
看图，根据图片及提示补全句子。
I want to go to Beijing. It's the city of our country. I will go there by .
But Xiaohong will go there by . It's faster. I take a to the train
station. We on Monday. And we will at 6: 00 in the evening. Wish me a good trip !
20℃、20kg的水，温度升高到70℃需要吸收多少J的热量；如果这些热量用燃烧氢气来提供，则要完全燃烧多少m3的氢气？（水的比热容为4.2×103J/（㎏·℃）、氢气的热值为1.4×108J/m3）．
.
. It's faster. I take a 
to the train