Barnes & Noble has reported a profit in the second quarter as it invested less in its Nook e-book reader and cost cuts offset lower sales. Its sales missed expectations, however, and its shares dropped more than three per cent in premarket trading. The company has invested heavily in its Nook e-book reader and digital library, but it has scaled back amid tough competition from Amazon’s Kindle and the Apple iPad. It introduced a new e-book reader, a $US119 Nook GlowLight, for the