Constructive team roles include （）.
A. encourager, initiator, and gatekeeper
B. information giver, devil's advocate, and clarifier
C. withdrawer, harmonizer, and blocker
D. summarizer, recognition seeker, and information seeker
One of the types of cost estimation is Order of Magnitude. This estimate （）.
A. is performed when detailed information is available
B. is performed when little if any information is available
C. is used in the beginning of the project conceptualization
D. B and C
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