How many U.S. states have active volcanoes?
12
5
4
5
3
2
4
5
3
2
4
5
3
2
4
5
3
1
2
4
5
3
1
2
4
5
3
1
2
4
5
3
1
2
4
5
3
1
2
4
6
5
7
3
1
2
4
6
5
7
3
1
2
4
6
5
7
3
1
2
4
6
5
7
3
1
2
4
6
5
7
3
1
8
2
4
6
5
7
3
1
8
9
2
4
6
5
7
3
1
8
11
9
2
4
10
6
5
7
3
1
8
11
9
2
4
13
10
6
5
7
3
1
8
11
12
9
2
4
13
10
6
5
7
3
1
8
11
12
9
2
4
13
10
6
5
7
3
1
8
11
12
9
2
4
13
10
6
7
3
1
8
11
12
9
2
13
10
6
7
1
8
11
12
9
13
10
6
7
1
8
11
12
9
13
10
14
6
7
1
8
11
12
9
13
10
14
6
7
8
11
12
9
13
2 states
128
4 states
7 states
128
128
5 states