10 pts
sara has just started using the internet. she would like to be a little more efficient. in 3–4 sentences, give sara some advice about how to be more efficient while using the web.

Function tipcalculate (slider, bill){  var tip = document.getelementbyid('tipamount');   var slideval = document.getelementbyid('slideval');   var bill = document.getelementbyid(bill).value;   var prcnt = slider * .01;       if (bill == null || bill == '') {      tip.innerhtml = ' enter an amount';       return false;   }  if(isnan(bill)) {      tip.innerhtml = ' enter a number';       return false;   }  if(bill > = 0){      tip.innerhtml = '$' + (bill * prcnt) .tofixed(2);   slideval.innerhtml = slider + '%';   }}

1. a 2. d3. a4. c5. c6. a7. c8. a9. b