Any sound from one focus of an ellipse reflects off the ellipse directly back to the other focus. This property explains whispering galleries such as Statuary Hall in Washington, D.C. The whispering gallery shown in illustration has the shape of a semi-ellipse. Find the distance sound travels as it leaves focus F and returns to focus F'.



A. 31 meters
B. 32 meters
C. 63.2 meters
D. 33.5 meters
E. 31.6 meters


Answer: E

Mathematics

You might also like to view...

Perform the addition or subtraction and give your answer in Hindu-Arabic form.

A. 119 B. 229 C. 219 D. 209

Mathematics

Provide an appropriate response.Graph the equation  for several values of a in order to get an idea of what these curves look like. (Try both  and  Show that the graph will have an inner loop for every a such that  and find the values of ? that correspond to the inner loop.

What will be an ideal response?

Mathematics

One of the values r (radius), d (diameter), C (circumference), or A (area) is given for a particular circle. Find the indicated value. Leave ? in your answer.d = 60 ft; C = ?

A. 120? ft B. 30 ft C. 120 ft D. 60? ft

Mathematics

Provide an appropriate response.A machine cuts a 12-in. diameter frozen pizza into slices whose sides form 45° angles at the center of the pizza. What is the surface area of each slice to the nearest square inch?

A. 12 in2 B. 15 in2 C. 28 in2 D. 14 in2

Mathematics