#untested 

open(QUESTIONS,">$questions") or die $!;
open(ANSWERS,">$answers") or die $!; 
open(READ_FILE,"$read_file) or die $!;

my($answer,$number);
while(<READ_FILE>) {
    if($_ =~ /^(\d+)/) {
        $number = $1;
    }
    if($_ =~ /^Answer: (\w)/) {
        $answer = $1;
        # print the last number found
        print ANSWERS "$number. Answer: $answer\n";
    }
    else {
        print QUESTIONS $_;
    }
}
close(ANSWERS);
close(QUESTIONS);
close(READ_FILE);
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