下列溶液中的氯离子数目与50 mL 1 mol/L的AlCl₃溶液中氯离子数目相等的是

A．75 mL 2 mol/L的CaCl₂

B．150 mL 1 mol/L的NaCl

C．150 mL 3 mol/L的KCl

D．100 mL 2 mol/L的NH₄Cl

If not attached to the nozzle,each low-velocity spray applicator on a vessel must be stowed（）.

A.in a protected area on the main deck

B.inside a machinery space near the entrance

C.next to the fire hydrant to which the fire hose is attached

D.on a rack inside the quarters near the entrance