AP 4-2 (Individual Tax Payable-Five Cases) Mr. William Norris is 45 years old. The following five independent cases make varying assump- tions for the 2021 taxation year with respect to Mr. Norris' marital status and number of depen- dants. In all cases, Mr. Norris had net income of $60,000, all of which is employment income with the exception of a CPP deduction of $290 (ITA 60(e.1)). Mr. Norris' employer withheld the required El premiums and CPP contributions. Case A Mr. Norris is married and his wife, Susan, has net income of $8,800. Susan's 73-year-old mother, Bernice, lives with them. Bernice has a mental infirmity that is not severe enough to qualify for the disability tax credit. However, it does make her dependent on William and Susan. Because of a large investment portfolio, Bernice had net income of $18,000 for 2021. Case B Mr. Norris is married and his wife, Susan, has net income of $4,410. They have one child, Martha, who is 10 years of age. Martha had no income during the year. During the year, the family had medical expenses as follows: William Susan Martha Total $1,200 1,600 350 $3,150