ANSWER:
65 hours.
Explanation:
The first thing is to calculate the number of hours a week, knowing that you spend 5 hours and 25 minutes per day.
A week, he works two days, so a week would be 10 hours and 50 minutes.
Now, it is 6 weeks therefore, we must multiply by 6 the time spent weekly, like this:
Mark has gardened for 65 hours.