Answer:
Net Income or Loss : a. 2019 = $53000  ; b. 2020 = $4000 loss ; c. 2021 = $43000 
Explanation:
Assets - Liabilities = Capital  (Closing/Opening)
458000 - 317000 = 141000 (2019 Closing Capital) 
Profit = Closing Capital - Opening Capital + Drawings - Additional Capital 
A.  2019 Opening Capital = 100000 (Given)
2019 Closing Capital = A - L = 458000 - 317000 = 141000 
2019 Profit = CC - OC - D + AC = 141000 - 100000 + 12000 =  53000 
B. 2020 opening capital = 2019 Closing Capital = 141000 
2020 closing capital = A - L = 538000 - 367000 = 171000 
2020 Profit =  CC - OC + D - AC = 171000 - 141000 - 34000 = 4000 Loss 
C. 2021 opening capital = 2020 closing capital = 171000 
2021 closing capital = A - L = 668000 - 467000 = 201000 
2021 Profit = CC - OC + D - AC = 201000 - 171000 + 25000 - 12000 = 43000