(a) **GST amount = $100**

Working: For a GST-inclusive total at the standard 10% rate, the GST component is the total divided by 11.
$1,100 ÷ 11 = $100

(b) **GST-exclusive price = $1,000**

Working: GST-exclusive price = total − GST = $1,100 − $100 = $1,000
(Check: $1,000 × 10% = $100 GST, giving $1,100 inclusive.)