How many US presidents were involved in the Vietnam war?
5
2
2
2
2
2
4
2
4
2
4
2
4
2
4
3
2
4
3
2
1
4
3
2
1
4
3
2
1
4
3
2
1
4
3
2
1
4
3
2
1
4
3
2
1
4
3
2
1
4
3
2
1
4
3
5
2
1
4
3
5
1
4
3
5
1
4
3
5
1
4
3
5
1
4
3
5
1
3
5
0
1
3
5
1
0
3
5
1
3
0
5
1
6
5
7
0
1
6
5
7
6
0
5
7
6
0
5
7
6
5
7
0
6
5
7
6
0
5
7
6
0
5
7
6
5
7
6
5
7
6
9
8
7
6
9
8
7
6
9
8
Two
7
6
Four
11
9
8
Two
7
6
Four
11
9
8
Two
7
6
Four
11
9
8
No
Two
7
6
Four
13
11
9
8
No
Two
7
6
Four
13
11
9
8
No
12
Two
7
14
6
Four
69
13
11
9
8
No
12
Two
7
10
14
6
Four
69