How hard will it be to take 2 summer online courses at the same time?

I’m taking E200 (Economics Class) and W131 (Writing Class) over the summer at the same time. The classes are each 6 weeks long, so I know the pace will be a lot faster.

How many hours a day will these 2 online courses take up during my day assuming that I want an A? How much time on the weekend will it take up?
From the looks of the syllabus there isn’t any homework and the grade is all based on quizzes and tests.

I did not take an economics class or composition class in my high school career, so I know almost nothing.

Bump, they are online college courses.