New Delhi, April 18 -- Shares of SpiceJet today surged to a fresh 52-week high, a day after Jet Airways shut down all flight operations indefinitely after lenders declined to extend more funds to keep it going. SpiceJet shares rose as much as 15% to a 52-week high of Rs.152 while another carrier InterGlobe Aviation, which operates IndiGo, also attracted strong buying. On the other hand, Jet Airways shares fell as much as 34%, in a sign that investors were sceptical about a revival despite lenders saying that they are "reasonably hopeful" that the bidding process for the grounded airline will end successfully....