【单选题】The parotid glands are located:
A.
inferior and anterior to the ears.
B.
at the base of the tongue.
C.
inferior to the liver.
D.
in the gastric mucosa.
E.
in the folds of the peritoneum.
【单选题】碳素工具钢的牌号T12A的含碳量( ) 。
【简答题】碳素工具钢随含碳量的增加其性能如何变化?
【判断题】40Cr表示含碳量0.40%的优质碳素工具钢。 ( )
【简答题】T12A是平均含碳量为( )的高级优质碳素工具钢。
【多选题】What are the following salivary glands?
【判断题】The parotid glands are in the floor of the mouth.
【判断题】碳素工具钢“T45A”中,钢的含碳量为4.5%。