What goes up must come down, and there are a lot of stocks that look vulnerable to a plunge right now. With the market at an all-time high, many stocks have seen their share price double or even triple in the last 12 months. Yet more than a few of these high-fliers look as if they’re teetering on the precipice and could topple over on the slightest bad news.Investors need to be careful as we enter the year’s second half. Many analysts are warning of choppy waters ahead for the market. Investment bank Morgan ...