Kristin earns $7 per hour at a video store and $10 per hour at a landscaping company. She must work at least 4 hours per week at the video store, but the total number of hours she works at both jobs cannot be greater than 15.
A. Let V represent the number of hours working at the video store and L represent the number of hours working at the landscaping company. Write a system of inequalities to represent the number of hours worked in one week.
B. Determine Kristin's maximum weekly earnings.