How many U.S. states share a border with Mexico?
4
5
3
2
5
4
3
2
5
4
3
2
5
4
3
2
5
4
3
2
5
4
3
2
1
5
4
3
2
6
1
5
4
7
3
2
6
1
5
4
7
3
2
6
1
5
4
7
3
2
8
6
1
5
4
7
3
2
8
6
1
5
4
7
3
2
8
6
1
5
4
7
10
3
2
8
6
1
5
9
4
7
10
3
2
8
6
1
5
11
9
4
7
10
3
2
8
6
1
5
11
9
4
12
7
10
3
2
8
6
1
5
11
9
4
12
7
13
10
3
2
8
6
1
5
11
9
4
12
7
13
10
3
2
8
6
1
5
11
9
4
12
7
13
10
3
2
8
6
1
5
11
9
4
12
7
13
10
3
2
8
6
1
11
9
4
12
7
13
10
8
6
1
16
11
9
12
7
13
10
8
6
1
16
11
9
12
14
7
13
10
8
6
1
128
128
128
2 states
4 states
128
8 states