About National Academy of Engineering's Grand Engineering Challenges for the 21st Century results of 10,000
18:11
06:35
13:38
06:51
14:18
09:38
03:36
12:12
12:12
05:20
04:22
02:10
03:20
03:03
03:17
37:43
12:07
02:40
04:35
14:27
05:02
04:20
12:15
10:53
26:22
24:50
14:07
06:15
07:47
05:13
11:52
11:09
10:01
05:41
28:35
08:01
11:07
49:31
04:22
65:37
02:34
15:34
08:36
10:29
11:12
05:08