Answer:
1. Jul-01	
Dr Investment in JBI Corp	$ 600,000	
Cr Cash $ 600,000
2. Nov-01
Dr Cash $ 5,000	
Cr Investment in JBI Corp $ 5,000
 
3. Dec-31
Dr Investment in JBI Corp $ 100,000	
Cr Investment revenue $ 100,000
Explanation:
1. Preparation of Rowan's entries to record the purchase of JBI shares
Jul-01	
Dr Investment in JBI Corp	$ 600,000	
Cr Cash $ 600,000
[To record investment in common shares of JBI Corporation]	
2. Preparation of Rowan's entries to record the receipt of its share of JBI dividends 
Nov-01	
Dr Cash [12,500*40%]	$ 5,000	
Cr Investment in JBI Corp $ 5,000
[To record receipt of dividends] 
3. Preparation of Rowan's entries to record the December 31 year-end adjustment for its share of JBI net income
Dec-31
Dr Investment in JBI Corp [$250,000*40%]	$ 100,000	
Cr Investment revenue $ 100,000
[To record share of net income for the year]