A closed organ pipe (closed at one end) is excited to support the third overtone.  It is found that air in the pipe has     

It is known that when closed pipe vibrates in fundamental mode, there are one node and one antinode.

When it vibrates in first overtone, there are two nodes and two antinodes.

When it vibrates in second overtone, there are three nodes and three antinodes.

When it vibrates in third overtone, there are four nodes and four antinodes.