Answer :
After subtracting 56 hours of sleep (8 hours per day for 7 days) from the total of 168 hours in a week, you are left with 112 hours for other activities, making option b the correct answer.
The question asks for the calculation of hours left for other activities in a week if you sleep eight hours per day. To find the solution, you must subtract the total hours of sleep from the total hours in a week. Given that there are 24 hours in a day and 7 days in a week, you would start with a total of 24 hours x 7 days = 168 hours per week.
Next, you would calculate the total hours spent sleeping by multiplying 8 hours of sleep per night by 7 nights,
giving 8 hours x 7 days = 56 hours of sleep per week.
Finally, you subtract the total hours of sleep from the total hours in a week to get the number of hours left for other activities: 168 hours - 56 hours = 112 hours.
Therefore, the answer to the question is 112 hours, which is option b.