Back to the Future or Rocky?

Are you a fan of Back to the Future? Of Rocky as well? Prove it! Select which quote belongs to which movie and see how good you are:

- We better back up. We don't have enough road to get up to 88.

- Roads? Where we're going, we don't need roads.

If my calculations are correct, when this baby hits 88 miles per hour... you're gonna see some serious shit.

- Why do you wanna fight?

- Because I can't sing or dance.

- It's Thanksgiving.

- Yeah, to you it's Thanksgiving; to me it's Thursday.

You're gonna eat lightnin' and you're gonna crap thunder!

- 1.21 gigawatts! 1.21 gigawatts. Great Scott!

- What-what the hell is a gigawatt?