Multi-turn tool-use scenario.
Tools involved: VehicleControlAPI

User requests (one per turn):
user: As I gear up for another delightful journey exploring the captivating waterways, I'm looking to convert 60 gallons of fuel into liters. Could you assist me with that conversion? I tend to work more comfortably with liters.
user: Thank goodness! With the conversion sorted, I'd appreciate your help in ensuring that my vehicle's tank is topped up with 20 gallons of gasoline.
user: Now, with the tank filled to my liking, I need to make sure my ride is prepared for this adventure. Could you help me start the engine, lock the doors, and engage the parking brake for a safe start?
user: Before setting off on this little expedition, can you do a quick tire pressure check for me? If any of the pressures fall below 33, kindly point me towards the nearest tire shop to get everything in tip-top shape before we roll.

Expected function call sequence:
VehicleControlAPI.gallon_to_liter
VehicleControlAPI.fillFuelTank
VehicleControlAPI.startEngine
VehicleControlAPI.check_tire_pressure
VehicleControlAPI.find_nearest_tire_shop