Construction Management - Engineering

Q1:

Pick up the correct statement from the following:

A Earliest expected time is denoted by TE

B Latest occurrence time is denoted by TL

C Contractual obligation time is denoted by Ts

D Latest occurrence time is taken as contractual obligation time

E All the above.

ANS:E - All the above.

Shouldn't it be Latest Finish Time be taken as Contractual Obligation time? Explain please.