function mostra(){
  var v1,v2,v3;
  if(km <= 2){v1=5.00;v2=6.00;v3=8.00;}
  else{var extra=km-2;v1=5.00+(extra*2.50);v2=6.00+(extra*3.00);v3=8.00+(extra*4.00);}
  if(desconto>0){v1=v1*0.9;v2=v2*0.9;v3=v3*0.9;}
  document.getElementById('p1').innerText="R$ "+v1.toFixed(2).replace('.',',');
  document.getElementById('p2').innerText="R$ "+v2.toFixed(2).replace('.',',');
  document.getElementById('p3').innerText="R$ "+v3.toFixed(2).replace('.',',');
  valor=cat=="Pop"?v1:cat=="Confort"?v2:v3;
  document.getElementById('preco').innerText="R$ "+valor.toFixed(2).replace('.',',');
  document.getElementById('km').innerText=km.toFixed(1)+" km • "+min+" min";
}

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