function calculate() {
var xamount=parseInt(document.forms[0].amount.value)
var xbasic=document.forms[0].basic.value
var xalta=document.forms[0].alta.value

if (xamount<15) {
xbasic="175.00"
xalta="52.50"
}

if (xamount>=15 && xamount<=24) {
var x = 24-xamount
var xb=5.5*x
var xa=1.65*x

xbasic=230-xb
xalta=69-xa
}

if (xamount>=25 && xamount<=50) {
var x = 50-xamount
var xb=5*x
var xa=1.5*x

xbasic=360.50-xb
xalta=108.15-xa
}

if (xamount>=51 && xamount<=75) {
var x = 75-xamount
var xb=4.5*x
var xa=1.35*x

xbasic=473-xb
xalta=141.9-xa
}

if (xamount>=76 && xamount<=100) {
var x = 100-xamount
var xb=4*x
var xa=1.20*x

xbasic=573-xb+".00"
xalta=171.9-xa+"0"
}

if (xamount>=101 && xamount<=150) {
var x = 150-xamount
var xb=3*x
var xa=.9*x

if (xamount==129 || xamount==139 || xamount==149) {
xbasic=723-xb+".00"
xalta=216.9-xa+".00"
}
else {
xbasic=723-xb+".00"
xalta=216.9-xa+"0"
}

}

if (xamount>=151 && xamount<=1000) {
var x = 1000-xamount
var xb=2*x
var xa=.6*x

xbasic=2423-xb+".00"
xalta=726.9-xa+"0"
}


document.forms[0].basic.value=xbasic
document.forms[0].alta.value=xalta

}