沙皇俄国是怎样向外扩张领土的？
产品质量主要分为哪几个方面？
对硬度在160HBS以下的低碳钢、低合金钢，为改善其切削加工性能，应采用的热处理工艺是（） 调质。 渗碳。 球化退火。 正火。
The number or name of a tank barge shall be（）. displayed in at least 4 different positions on the barge。 carved on a wooden board and attached to the barge's hull。 displayed as close to the navigation lights as possible。 displayed at the highest point of the barge's hull such that it can be seen from either side。
When checking the liquid level in a tank, you should position yourself （）. on the windward side of the opening。 on the leeward side of the opening。 at a right angle to the wind direction。 so that the obstruction of your body will protect you from the fume。
哪些行业是兴业租赁的主要投向行业（）
