Uji Level

 var nilai =prompt("masukkan nilai anda")
    var grade =""

    if (nilai >= 98){
    grade = "A"
    } else if(nilai >=80){
    grade = "B"
    } else if(nilai >=75){
    grade = "C"
    } else if(nilai >= 60){
    grade ="D"
    }else if(nilai >= 40){
    grade ="E"
    }else if(nilai >= 0){
    grade = "F"
    }

    document.write("<p>Grade anda adalah :",grade, "<p>");

        alert("anda harus masukkan nilai yg benar")
    if (pilihan == true){
        alert('anda telah mengulang')
    }else{
        alert('anda tidak menulang')
    }