Answer:
She made $768 last week. She made $39,936 in 2011.
Explanation:
She sold 6400 last week.
She earns 12% of the amount sold per week.
So, 12% of 6400 is $768.
Now, there are 52 weeks in a year.
And she made 768 per week.
So, for the whole year, we multiply the amount made in 1 week by 52.
So, 52*768 is $39,936.