Answer:
mCEA = 90ᴼ, as CEA forms a right angle, and by definition, right angles measure 90ᴼ.
The angle CEF is classified as a straight angle as it combines two right angles (CEA and AEF), equating to 180ᴼ altogether. Straight lines are defined to measure 180ᴼ.
AEF is determined to be a right angle as CEA is already a right angle, and since CEF is a straight line, AEF must also be a right angle.
Answer: observational study
Step-by-step explanation: