下述下颌第一恒磨牙髓室形态特征中哪个是正确的()。
A.龈径最大
B.近远中径大于颊舌径
C.颊舌径大于近远中径
D.颊舌径最大
E.龈径大于颊舌径
参考答案:B
My son ____ coke , but now he ______ milk.
A.used to drink; is used to drinking
B.used to drinking; drinks
C.used to drink used to drink
D.used to drink; is drinking
M(NO3)2热分解的反应方程式为2M(NO3)22MO+4NO2↑+O2↑,加热29.6g M(NO3)2使其完全分解,在标准状况下得到2.24L氧气,则M的摩尔质量是( )
A.24 g/mol
B.24
C.64 g/mol
D.64