Question

K.P.L.C. sell power to its customers in form of units as follows;

Kshs 13 per unit for the first 50 units
Kshs 15 per unit for the 2nd 50 units
Kshs 25 per unit for the 3rd 50 units
Kshs 40 per unit for the 4th 50 units
Kshs 75 per unit for any other unit.

a) Form a function u(s) i.e a function is expressing units in form of a shilling and used to comprise units a customer will buy with:
i) 1820 shillings
ii) 5,000 shillings