MILAN—The mayor of Italy’s financial capital Milan demanded answers on Monday over why a fire was able to rip through an apartment block and melt its cladding, comparing it to the Grenfell Tower fire in London that killed 71 people four years ago. Firefighters said everyone managed to escape the 18 story building in the south of Milan, which was gutted by the blaze that broke out on Sunday afternoon. Among the residents in the high rise building was rapper Mahmood, winner of the 2019 San Remo music festival with his international hit “Soldi.” Witnesses have said the fire, which started on the 15th floor, quickly surged through the outside cladding of the building. Video of the blaze showed panels melting off the building in liquefied clumps. “The tower was built just over 10 years ago and it is unacceptable that such a modern building should have proved totally vulnerable,” …