How to know if a problem is permutation or combination?

If the order matters it is a permutation. For example: if you are selecting 3 people to be on a committee it doesn't matter what order you select them, but if you're selecting three people to be president, vice president, and secretary the order in which you choose them matters the first person being president, the second person being vice president, and the third person be secretary

At a constant it will take one hour to travel 32 mi.at that speed it will take 1/2 hr to travel the remaining 16 mi.it will take 1+1/2 hr to travel the 48mi @ 32mph.so 1 hr = 60 min& 1/2 hr = 30 min1+1/2 hr = 90 min.there are 60s in each 90 × 60 = 3600 seconds.the real question seriously is he why are they driving so slow? ! lol.