Today is _ _ cool.[ ]
A. a lot of
B. a lot
C. some
D. rather
BD
玻璃电极内部缓冲液的作用是使玻璃膜内侧氢氧根活度保持不变。()
观察图,意大利航海家哥伦布的航海路线是()
A.①
B.②
C.③
D.④