Protection from Energy Vs Resist Energy

[Olethros]

I get that one absorbs all damage up to a limit from a single enery source and one removes the first 10(or more) points of damage from each application of the energy source.

My question is, In the spell discription of protection from energy, it says you are protected from a source of energy you "specify when you cast it," where resist energy simply says a source of energy "you select." Does this mean that you must specify the type of energy resisted when the spell is memorized/prepaired/etc? What about wand/scroll casting? Does a wizard need to create seperate scrolls for each energy type if he wants to be ready for anything?

[Variable Arcana]

- With both spells, you normally select the energy type at casting.
- With a potion, the type is selected by the brewer ("The character taking the potion doesn’t get to make any decisions about the effect —the caster who brewed the potion has already done so." -- SRD under Potions; note that resist energy is listed as "resist energy (type)" in the potions list)
- With a scroll, the type can be chosen at activation time (I base this on the lack of "(type)" restrictor in the scroll list, and the lack of an equivalent sentence to that in the potions section.)
- I'd guess that the same is true of wands (though a wand of resist energy isn't listed...)

[Hamster_Ninja]

In the case of a scroll, it is cast (I beleive) as if you had cast the spell yourself. I'm not sure on wands, but with potions you need to spell out every effect it will have, so there you would need to pick the energy type.
Edit: Anyone know whats plagueing these parts? The town I left behind's been ninja'd to the ground.