Top$-$down estimates $($You may select more than one answer. Single cllck the box with the qu for a correct answer and double cllck the box with the question mark to empty the box for question mark wIII be automatically graded as incorrect.$)$

are used in the project conceptual phase

depend on surrogate measures such as weight or square feet or ratios

do not consider individual activity issues and problems

are good for rough estimates

can help select and prioritize projects

are made by people familiar with the task

help to gain buy$-$in on the validity of the estimate

improve the accuracy of the estimate

$?$ should be preferred if estimating cost is reasonable