In each of the following parts, you are given the original price of a good. Calculate the $10%$10% goods and services tax (GST) applicable, rounding to the nearest cent if necessary.
$\$80$$80
$\$37$$37
$\$95$$95
$\$59$$59
Calculate the GST-included sales price for an item with an original price of $\$20$$20.
John received a bill of $\$68$$68 for consultation and $\$10$$10 for herbal supplements from a medical professional. If GST is only applied to the consultation fee, what is the total bill that John must pay? Give your answer correct to two decimal places.
Calculate, to the nearest cent, the GST on an item with a sales price (which already includes GST) of: