<?php

require '../service/PaycheckService.php';
$salary = $_GET['salary'];
if (is_numeric($salary)) {
    $inss = PaycheckService::getINSS($salary);
    $baseSalary = PaycheckService::getBaseSalary($salary);
    $ir = PaycheckService::getIR($baseSalary);
    $liquidSalary = PaycheckService::getLiquidSalary($salary);
}
$calculation = array('INSS' => $inss, 'IRPF' => $ir, 'liquidSalary' => $liquidSalary);
echo json_encode($calculation);
<?php

require 'PaycheckService.class.php';
$salary = $_GET['salary'];
if (is_numeric($salary)) {
    $inss = PaycheckService::calculateINSS($salary);
    $irpf = PaycheckService::calculateIRPF($salary - $inss);
    $liquid = PaycheckService::calculateSalary($salary, $inss, $irpf);
    $result = array("inss" => $inss, "irpf" => $irpf, "liquid" => $liquid);
}
echo json_encode($result);