urgent plz

Write a self calling PHP page that asks for the units(kW) of electricity used and then calculates and returns the bill.

Conditions:

• For the first 40 units TL 3.00/unit
• For the next 50 units TL 3.50/unit
• For the next 50 units TL 5.10/unit
• For the units above 140 TL 5.50/unit