Casio MS-80TV Scientific Calculator "change gst" Questions

HOW DO I CHANGE GST TAX RATE ON CASIO MS-8TV CALCULATOR How do I change the tax rate on my calculator MS-8TV

how do I change the GST to 12.5% Thanks Brent I solved my problem with the information I received off the web site. Thank you Brent

I need to change the GST from 12.5% to 15%??? hold the % (rate set) down for approx 3 sec then put in 15% and hold the % key again should do it