Whats the annulus of the shaded area? ​

Can someone me do math because i am having a breakdown rn because i don’t get it

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?

How long must $542 be invested at a rate of 7% to earn $303.52 in interest? in a easier way