If to, tp and tm are the optimistic, pessimistic and most likely time estimates of an activity respectively, the expected time t of the activity will be

• A. <img src="/_files/images/civil-engineering/construction-management/73-19-68-1.png">
• B. <img src="/_files/images/civil-engineering/construction-management/73-19-68-2.png">
• C. <img src="/_files/images/civil-engineering/construction-management/73-19-68-3.png">
• D. <img src="/_files/images/civil-engineering/construction-management/73-19-68-4.png">
• E. <img src="/_files/images/civil-engineering/construction-management/73-19-68-5.png">