Consider following code snippet:

var ch1 = 'b';
var ch2;
switch(ch1) {
  case 'a':
     ch2 = '1';
  case 'b':
     ch2 = '2';
  case 'c':
     ch2 = '3';
     break;
  default:
     ch2 = '4';
}

What will be the value of ch2 variable?