How is the surging price of commodities affecting the global economy?

Commodities - the raw materials that power business around the globe - are surging in price. And that suggests investors betting on a prolonged expansion—and a potential rebound in inflation. The S&P GSCI, which tracks commodity prices has advanced 12% this year. Copper and oil have gained more than 10% and 17%, respectively. Gold is also posting fresh records, rising 13% to $2,332 a troy ounce. So what's going on?Also, in the programme, the presenter Roger Hearing finds out why some politicians have pushed back against New York City’s congestion charging plan.