“Where is David?” “He is upstairs ______ ready to go out.”

A．to get

B．getting

C．to be getting

D．having got

“T746”（十二烯基丁二酸）防锈剂的分子式为（）。

A.C₆H₂（C₄H₉）2CH₃OH

B.C₁₄H₂₆（COOH）₂

C.C₆H₄（COOH）₂

D.C₁₄H₂₆COOH