When the door of the Chapel of the Mausoleum in Hamilton,Scotland, is slammed shut, the last echo heard by someone standingjust inside the door...

When the door of the Chapel of the Mausoleum in Hamilton,Scotland, is slammed shut, the last echo heard by someone standingjust inside the door reportedly comes 22.0 s later.(a) If that echo were due to a single reflectionoff a wall opposite the door, how far from the door would that wallbe (in km)? (b) If, instead, the wall is 27.1 maway, how many reflections (back and forth) correspond to the lastecho? Assume the speed of sound is 345 m/s.