How many Back to the Future movies are there?
3
3
3
3
3
3
2
4
3
2
4
5
3
2
4
5
3
2
4
5
3
2
4
5
3
2
4
5
3
2
4
5
3
2
4
5
3
2
4
5
3
2
1
4
5
3
2
1
4
5
3
2
6
1
7
4
5
3
2
6
1
7
4
5
0
3
2
6
1
7
4
5
3
2
6
1
7
4
5
3
2
6
1
7
4
5
2
6
1
7
4
5
2
6
1
7
4
5
2
6
1
7
4
5
2
6
1
7
4
5
8
6
1
7
5
8
6
1
7
8
6
1
7
8
6
1
7
8
9
6
1
7
8
9
6
1
7
10
11
8
9
6
1
7
10
13
11
8
9
6
1
7
10
13
11
8
9
6
1
7
10
13
11
8
9
12
6
7
10
13
11
8
9
12
6
7
10
13
11
8
9
12
10
13
11
8
9
12
16
10
13
14
11
8
66
62
59
132
57
512