why is only the first part of my code passing ?!

/*this is my code*/ 
var egypt = prompt(" What is the capital of Egypt? ");
var kuwait = prompt(" What is the capital of Kuwait? ");
var thailand = prompt(" What is the capital of Thailand? ");
var turky = prompt(" What is the capital of Turky? ");
var life = prompt(" What is the most defecult game in the world ");
var correct = 0;

/* checking the answers*/
if (egypt.toUpperCase() === cairo) {
  correct += 1;
}
if (kuwait.toUpperCase() === kuwait){
    correct += 1;
}
if (thailand.toUpperCase() === bangkok) { 
  correct += 1;
}
if (turky.toUpperCase() === istanbul) {
  correct += 1;
}
if (life.toUpperCase() === life) {
  correct += 1;
}
/* out put the result */
document.write('<h1> Yo got ' +correct+ ' out of 5 questions correct </h1>');
/* ranking */
if ( correct === 5 ) {
  document.write("<h1><strong> you earned a gold crown! </strong></h1>");
} else if ( correct >= 3) {
  document.write("<h1><strong> you earned a silver crown! </strong></h1>");
} else if ( correct >=1 ) {
  document.write("<h1><strong> you earned a bronze crown! </strong></h1>");
} else {
  document.write("<h1><strong> YOU LOST </strong></h1>");
}