— John seems happy, even though his wife left him and he lost his job.

— I think he __________ to put on a brave face.

A．will try

B．has tried

C．had tried

D．is trying

已知20℃时，氯化钠的溶解度为36g，

（1）20℃时，饱和氯化钠溶液中，溶质、溶剂与溶液的质量比为                        ；

（2）若要配制20℃时饱和溶液68g，则需氯化钠                g，水                 g．