Answer: See explanation
Step-by-step explanation:
a. Even though firm B received a cash of $522, only $22 which is the interest will be taxable as the $500 which is the principal isn't taxable.
b. Even though Firm B got $600 cash, there'll be no taxable income as the receipt brought about a liability. Hence, taxable income is 0.
c. Even though Firm B got $10000 cash, there'll be no taxable income as the receipt brought about a liability and the net worth wasn't increased. Hence, taxable income is 0.
d. The taxable income here will be $888.