Answer to Question define-11

Here is one possible definition.
  double seconds(int ms)
  {
    double x = ms;
    return x/1000.0;
  }
It is not really necessary to have variable x. You can convert from int to double using (double), and write
  double seconds(int ms)
  {
    return ((double) ms)/1000.0;
  }
You can also perform an operation between an integer and a real number. The integer will automatically be converted to a real number. So you can write
  double seconds(int ms)
  {
    return ms/1000.0;
  }
But
  double seconds(int ms)
  {
    return ms/1000;
  }
does not work because it divides two integers, so it throws away the fractional part.