(A) Cash is liquid assets. It is differnece between receipt 
and disbursement of any cash transaction. eg. rent paid in 
cash of rs 10000/-p.m. Profit is combine effect of real and 
nominal accounting transaction related to expenses and 
income of mercantile business.  

(B) Net profit comes after crediting all income and 
deducting debit expenses from them. This profit is wealth 
of business for the perticular year. Wealth has credit for 
the business therefore netprofit adds or comes under 
capital account.