In the right triangle shown, How long is AB?
Answer exactly, using a radical if needed.

Which statement accurately explains whether a reflection over the y-axis and a 270° counterclockwise rotation would map figure acb onto itself? a coordinate plane with figure acb with point a at 1, 1, c at 3, 4 and b at 5, 1 yes, a″c″b″ is located at a″(1, 1), c″(4, 3), and b″(1, 5) yes, a″c″b′ is located at a″(1, 1), c″(3, 4), and b″(5, 1) no, a″c″b″ is located at a″(1, 1), c″(4, 3), and b″(1, 5) no, a″c″b″ is located at a″(1, 1), c″(3, 4), and b″(5, 1)

Thales was an ancient philosopher familiar with similar triangles. one story about him says that he found the height of a pyramid by measuring its shadow and his own shadow at the same time. if the person is 5-ft tall, what is the height of the pyramid in the drawing?

Math it's appreciated. (picture provided)