About National Academy of Engineering's Grand Engineering Challenges for the 21st Century results of 10,000
02:01
04:08
03:15
01:50
15:20
12:34
06:41
01:38
08:13
05:07
09:49
03:13
12:32
02:58
03:31
02:16
14:44
19:23
01:50
09:22
01:33
05:04
05:43
05:48
08:56
02:10
01:35
05:34
11:03
06:57
08:59
05:44
01:36
04:52
02:01
03:03
11:11
14:02
15:46
03:04
34:20
05:15
07:38
01:42
14:36
12:47