She works 25 hours a week and earns 15 dollars each hour, so she earns 25 x 15 dollars a week, which is 375 dollars, since her regular hours are weekday hours, which are not on sunday.
If she works an additional 8 hours on Sunday, however, she will make double pay, so she will earn 30 dollars an hour. 30 x 8 = 240.
240 + 375 = 615 dollars.
The answer is 615.
Hope this helps.