How to assign periorities to electric devices in Matlab

I have three electric devices like Electric Heater , TV and washing Machine.

I want that first of all TV should be assigned High Periority and it should be switched on for 3 hours

After that Washing Machine must be Assigned Medium Periority and it should switched on for 2 hours.

In the end Electric Heater should assign low periority and it should switched on for 2 hours.

Please help me out in this situation. I have no idea of assigning periorities in Matlab and i have to submite the project in three days .