1. Horn of Renew gives a buff for a certain amount of time that heals the user and everyone in range. How long exactly is this buff? (No upgrade)
2. Increased Duration upgrade, how long does it make the buff last? How long is that 25% increase?
3. Challenge (charged), will it work at 8m even if I did not take the Increased Ranged upgrade?
4. Protective Shield (charged), is it affected by Increased Duration upgrade? Will the 2 sec increase also?

Sorry for all the noob question guys, new here. Don't wanna waste those 7 silver coin thing on resetting my character.

Thanks!