To calculate the missing item in each case, you need to reconcile the equity at the beginning and end of the year, considering owner's investments, profit or loss, and owner's withdrawals.

Case b:

Equity, January 1 + Owner's investments - Owner's withdrawals + Profit (loss) = Equity, December 31

Substitute the given values:

0 + 62,000 - (29,000) + 17,750 = 58,000 (for the first column)

0 + 33,500 - (22,000) + 32,500 = 50,500 (for the second column)

0 + 39,500 - (16,750) - 4,700 = 34,000 (for the third column)

The missing item in each case is the initial equity.