Travis's superior, Adam, asked how long it takes for him to finish a project. Travis anticipates a best-case scenario of 4 hours, a worst case scenario of 8 hours and a probable scenario of 5 hours. Using the formula to calculate the expected time, Travis should tell his supervisor the project will take? a. 5.3 hours b. 2.8 hours c. 6.8 hours d. 4.8 hours e. 8.7 hours