Correct Answer - Option 4 : Supplementary estimate
Explanation:
Supplementary estimate
i) It is a detailed estimate of additional work and is prepared when additional works or changes are required to supplement the original works, during the execution of work.
ii) Then a fresh detailed estimate of additional works is prepared in addition to the original works.
iii) The abstract should show the amount of the original estimate and the total amount including the Supplementary amount, for which sanction is required.
Revised estimate
It is a detailed estimate and is required to be prepared under any one of the following circumstances:
i) When the original sanctioned estimate is likely to exceed by more than 5 %.
ii) When the expenditure on work exceeds or likely to exceeds the amount of administrative sanctioned by more than 10 %.
iii) If there is a change of rate or quantity of materials.
iv) Major additions or alterations are introduced in the original work.