What do these mean here?
1. What does '30-40-year concessions' here mean?
Though potentially lucrative, airports tie up a lot of capital, which is why governments around the world are selling them. Some are being listed on stockmarkets, others sold to private investors. The Japanese government is selling 30-40-year concessions to run some of its airports.
2. Does 'bridges' here mean ordinary bridges or something else?
Best of all is the bonus that comes from being a monopoly. Returns from well-run airports tend to be in the double digits, markedly higher than more boring assets like bridges.