Greece’s financial crisis and signs of growing opposition to austerity in Spain sent the euro to its lowest level in a month on Tuesday, while shares and commodities took a knock as the dollar powered higher. Europe’s main markets returned to action after a long weekend with the mood unsettled by Sunday’s strong local election showing by anti-austerity parties in Spain, while bets were put back on a U.S. rate hike this year after having been all but cancelled over the past two months.