How many states do not share any borders with any other U.S. state?
2
5
2
5
3
2
5
3
2
5
3
13
2
5
3
13
2
7
5
3
13
2
7
9
5
3
13
2
7
9
5
10
1
3
13
4
2
7
9
5
10
1
3
13
8
4
2
7
9
5
10
1
3
13
8
4
2
7
9
5
10
1
3
13
6
8
4
2
7
9
5
10
1
3
13
6
8
4
2
7
9
5
10
1
3
13
6
8
4
2
7
9
5
10
1
3
13
6
8
4
11
2
7
9
5
10
1
3
13
6
8
4
11
2
7
9
5
10
14
1
3
13
6
8
4
11
2
7
21
9
5
10
14
1
3
13
6
8
4
11
2
7
21
9
5
10
14
1
3
13
6
8
4
11
2
7
21
31
9
5
10
14
1
3
13
6
8
4
11
2
7
21
31
20
9
5
10
14
1
3
17
13
6
8
29
4
11
2
7
21
31
20
12
9
10
14
1
3
17
13
13 states