What are the perimeter and the area of the square?

The center of the circumscribed circle lies on line segment and the longest side of the triangle is equal to the of the circle.

A3-dimensional figure has a square base and 4 lateral faces that meet at a point. explain the difference between the cross sections when a slice is made perpendicular to the base through the vertex, and when a slice is made perpendicular to the base and not through the vertex

Me on this i beg you on this to answer!