it depends
if its your goal
A brisk walk is about 4MPH, it would take 3hrs 18minutes at that pace.
30 minutes.
Yes, it is. Running on a treadmill will certainly help, but treadmills don't have the incline variability of natural terrain, so your body won't be prepared to run the half-marathon. Training on a treamill is a great way to prepare for a mini marathon. It would also be a good idea to get some actual track time in if possible.
A negative split in a marathon is where you run the first half or maybe even the first 10 miles of the race slower than your goal pace. Then the last half of your marathon, you pick up the pace, running faster than your goal pace to make up for the lost time from running slower in the first half of the race. This is a good technique to running a marathon because since it is such a long distance you conserve a lot of energy in the first half, and save it for the last part of the race. Running slower then faster than your goal pace will still get you your goal time if done correctly, you are just running in a different way.
2:05
10-year-old Drew Dahlin of Green Bay, WI ran the USATF sanctioned 2012 Green Bay Cellcom Half Marathon in a time of 1:38:42.
11-Year-Old Drew Dahlin of Green Bay, WI ran the USATF sanctioned 2013 Green Bay Cellcom Half Marathon in a time of 1:34:23.
9 -year-old Drew Dahlin of Green Bay, WI ran the USATF sanctioned 2011 Green Bay Cellcom Half Marathon in a time of 1:44:48.
8-Year-Old Drew Dahlin of Green Bay, WI ran the USATF sanctioned 2010 Green Bay Cellcom Half Marathon in a time of 1:54:41.
A good pace, not too fast though. Go out and practice, time yourself, work up to the two hour time limit. You can do it.