He lived 9 months in Portugal and 5 months in Brazil. This is because 130*9 + 150*5 = 1920.
Cost = (3500 W)·(1 kw/1000 W)·(10 hrs/day)·(30 day/month)·($0.13/kw-hr)
Cost = (3500·1·10·30·0.13 / 1000)·(W·kW·hr·da·$ / W·da·month·kw·hr)
Cost = <em> 136.50 $/month</em>
Ok, so she started off with $5.00.
She bought milk for $2.99.
She buys bread, which costs $1.50.
Subtracting the money she wasted, the total would be $0.51.
The only thing she could buy is 5 pieces of gum for 25 cents.
Her change will be $0.26.
Hope this helps!
If it goes through the origin of a graph