In relation to the taxable income formula, which of the following statements is least correct?

a$.$

You calculate your taxable income by adding up all your assessable income and adding up all your deductions and subtracting the total of your deductions from

your assessable income.

b$.$ Assessable income includes ordinary income and statutory income, but does not include exempt income.

c$.$ Goods and services tax $($GST$)$ is generally disregarded when calculating the assessable income of a taxpayer.

d$.$ There are general deductions, specific deductions and other deductions.

e$.$ Foreign resident $($non$-$resident$)$ taxpayers are generally required to include Australian source income when calculating their taxable income.