How many major rivers are there in Africa?
7
4
3
4
3
4
5
3
4
5
3
4
5
3
4
5
3
2
4
1
5
3
2
4
1
5
3
2
4
1
5
3
2
4
6
1
5
3
2
4
6
1
5
3
2
4
6
1
5
3
2
4
6
1
5
3
2
4
6
1
7
5
3
2
4
6
1
7
5
3
2
4
6
1
7
5
3
2
4
6
1
7
5
3
2
4
6
1
7
5
9
3
2
4
6
1
7
5
9
3
2
8
4
6
1
7
5
0
9
3
2
8
6
1
7
5
9
2
8
6
1
7
5
9
2
8
6
1
7
9
10
2
8
11
6
1
7
9
10
2
8
11
6
1
7
9
12
10
2
8
11
6
1
7
9
13
12
10
8
11
6
7
9
13
12
10
8
11
6
7
9
13
12
10
8
11
6
7
9
13
12
10
8
11
7
9
13
12
10
8
11
7
9
13
66
102
63
62
59
123
132