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MARKETABLE SECURITIES (Schedule of Investment Income) (Details) - USD ($)
12 Months Ended
Jul. 31, 2021
Jul. 31, 2020
Investments, Debt and Equity Securities [Abstract]    
Interest income $ 850 $ 20,446
Dividend income 98,915 96,569
Gain on sale of marketable securities 73,783 28,546
Total $ 173,548 $ 145,561