Answer:
Sheffield Co  	
statement of stockholders' equity    
for the year ended 31th December 2020    
                  Common Stock	RE            OCI   Total
Balance Jan 1	360,400      92,040	86,000	538,440
Net Income                                 167,900                 167,900
unrealized loss                                              -53,700     -53,700
Dividends                        -11,670             -11,670
Stock issued
Balance, Dec 31	360,400      248,270          608,670
Explanation:
We need to calcualte the net income:
sales revenue           777,  100
cost of goods sold  (520,000)
operating expenses <u> (89,200) </u>
Net Income                167,900
This will go into retained earnings
Dividends will also impact on retained earnings
Unrealized holding loss on available-for-sale debt securities for 2020 of $53,700. 
This will modify the other comprehensive income.
The rest, will be post the beginning balance and include this variation.