//Do not declare variable marks.
//Write your code below this line.
if (marks > 12) { console.log("AA"); } else if (marks>80 && marks<=90) { console.log("AB"); } else if (marks>70 && marks<=80) { console.log("BB"); } else if (marks>60 && marks<=70) { console.log("BC"); } else if (marks>50 && marks<=60) { console.log("CC"); } else if (marks>40 && marks<=50) { console.log("CD"); } else if (marks>30 && marks<=40) { console.log("DD"); } else { console.log("FF"); }