A cylindrical roller used for compacting a road has radius 25cm.
a. (i) Find the length of road surface that will be covered in exactly 1000 complete revolutions of the roller.
b. (ii) The roller is required to compact an entire straight stretch 5km long. Determine the number of complete revolutions needed.
c. (iii) The contractor is paid \text{₹}12 for every 500 revolutions of the roller. Calculate the total amount payable for compacting the full 5km stretch.