Spanish help with affirmative informal commands?

Question

Thanks for reading!
I have a question that my textbook isn't helping me with. but first, am I doing it right...
¿Preparo los pasteles?
~ Si, Preparalos.

Now, what do I do when the word isn't la, but el? Do I just change it into Lo? example...
¿Abro el refrigerador?
~ Si, Abralo???????

Thanks for helping me, as I really do suck at spanish =P

Answer 1

You are correct, but don´t forget the accents
prepáralos (informal)
prepárelos (formal)

ábrelo (informal)
ábralo (formal)


When it is masculine just change the ending to
"lo" singular or "los" plural

Answer 2

1.- ¿Preparo los pasteles? Sí, prepáralos (tú).
Sí, prepárelos (usted)

2.- ¿Abro el refrigerador? Sí, ábrelo (tú).
Sí, ábralo (usted).

Answer 3

You've got it. That´s correct.
Masculine nouns are substituted by "lo"

ex.: ¡Contesto el mail?
Si, contéstalo.

Answer 4

Yes you are half right but make sure to place the ' over the right syllable. Ask me if you don't know why.
Prepáralos
Ábrelo