An architectural blueprint for a plaza features a circular water fountain and a stone promenade. The fountain area is defined by a major sector ABCOAABCOAABCOA of a circle with centre OOO, while the promenade is a triangle AODAODAOD adjacent to it. The following information is given:
The major sector ABCOAABCOAABCOA has an arc ABCABCABC that starts at CCC and ends at AAA.
Find:
the size of angle ∠AOD\angle AOD∠AOD, in radians, to 3 decimal places,
the length of the arc ABCABCABC of the fountain, in metres, to one decimal place,
the total area of the plaza feature (fountain and promenade), in m2\text{m}^2m2, to one decimal place.
