How does the STAB + Weather condition and that kind of things work?

Question

Take Torkoal:
Torkoal is a fire-type
Drought powers up fire-type moves with 50%
It's STAB does the same.
When Torkoal would use Lava Plume, with what base power would Lava Plume strike?
Two options:
Option 1: 80 + 40 + 40 (Base power + weather boost + STAB) = 160
Option 2: 80 + 40 = 120 + 60 (Half of 120) = 180 (Base power + weather boost/STAB = 120 + STAB/weather boost)

Answer 1

80 Base Power of Lava Plume x 1.5 (50% increase) STAB x 1.5 (50% increase) Weather Condition (i.e. Drought)

80 x 1.5 = 120 x 1.5 = 180

Answer 2

So..
STAB stands for Same Type Attack Bonus, and means that whenever your Torkoal uses a Fire type move, the move will be boosted by 1.5x (which basically means the move's power will be multiplied by 1.5).
Drought powers up Fire-type moves by 1.5 which also means the move's power will be multiplied by 1.5.
Lava Plume has 80 base power, so...

80 x 1.5 = 120 (with STAB bonus),
120 x 1.5 = 180 (with Drought bonus)

The total base power of Lava Plume by Torkoal in Sun is 180.

Comments

Actually I already knew what STAB means, as I won't awnser something withouth knowing what it means, and I also knew what weather boost and STAB does, like the description says. You don't have to explain something if I noted it in the question description. But thank you for awnsering anyway.