When they say per week what that mean?

Question

2×10³=

 

Answer 1

10³ = 10×10×10 = 1000

 

2 × 10³ = 2 × 1000 = 2000

 

Not sure about your question about "what does per week mean"?  It means in a week, such as how you much you earn in a week, or how much you spend in a week, etc.  You need to be more specific about your question.