Cramer's lightning round: Buy the stock of Boeing
American Airlines : "I think that that stock has now moved up too much. They did the giant equity offering, they had to do it, they had to raise money. I don't know how much money they're losing. ... My suggestion is: buy the stock of Boeing because, if it really comes back, everyone is short planes and needs them."

American Tower : "I like Crown Castle more. ... The reason why AMT's going down is because, like Crown Castle, it trades off of interest rates. It shouldn't, these are growth companies, but that's what happens. I would prefer you to be in CCI than I would you to be in AMT."

Opko Health : "I don't know what to say, Keith. I'm glad you brought this up. ... I'm beginning to believe, you don't want to hear this, but the day is not arriving, at least not anytime soon."

General Motors : "That company could be worth far more. ... I think it's real good."

Surface Oncology : "I candidly am not in the genomics oncology business, but I know that this is where, if you wanted to have a speculative stock, it seems like a very good place to be."

S&P Global : "I think SPGI is a remarkable company. I like this acquisition, I think it's great. Some of these high-growth companies have started to roll over. People are scared. I think you should actually buy some SPGI."