Jessamyn bought 3 notebooks that cost $2.25 each and a pen that cost $0.75. Sales tax on her purchases was 6%. What was the amount of the sales tax? $0.54 $0.75 $0.18 $0.45

Jessamyn bought 3 notebooks that cost $2.25 each and a pen that cost $0.75. Sales tax on her purchases was

6%. What was the amount of the sales tax?
$0.54
$0.75
$0.18
$0.45