Table:
pumpernickel bread crumbs	$5 per lb

sourdough bread crumbs	$5 per lb

whole grain bread crumbs	$4 per lb

rye bread crumbs	$5 per lb

Inspect the given table and provide the values of cells found at the specified positions, determined by row and column indices. Show the cell value in the JSON format {"row_id":"m", "column_id":"n", "cell_value":"<Corresponding Cell Value>"}.
Positions:
the 1st row and the 2nd column,
the 4th row and the 2nd column,
the 1st row and the 1st column,
the 2nd row and the 1st column,
the 2nd row and the 2nd column,
the 3rd row and the 1st column,

The extracted cell contents are listed below.
{"row_id":"1", "column_id":"2", "cell_value":"$5 per lb"}
{"row_id":"4", "column_id":"2", "cell_value":"$5 per lb"}
{"row_id":"1", "column_id":"1", "cell_value":"pumpernickel bread crumbs"}
{"row_id":"2", "column_id":"1", "cell_value":"sourdough bread crumbs"}
{"row_id":"2", "column_id":"2", "cell_value":"$5 per lb"}
{"row_id":"3", "column_id":"1", "cell_value":"whole grain bread crumbs"}