3. Retrograde motion is something that was observed to happen to the planets motion through the sky.      a) What is retrograde motion of the planets?      b) How did Ptolemy try to explain retrograde motion?      c) How does Copernicus’s model explain retrograde motion?

22. An electron emits a ______ when it transitions from a higher energy level to a lower energy level in an atom?

28. Adaptive optics are used to correct which of the following problems?

An airplane flies at an altitude of 6  miles towards a point directly over an observer. Consider  and  as shown in the following figure. The speed of the plane is400 miles per hour. Find  when  miles. Round your answer to three decimal places. ​ ​

Assume that  x  and  y  are both differentiable functions of  t  . Find  when  and  for the equation. ​

Find the points at which the graph of the equation has a vertical or horizontal tangent line. ​ ​

An airplane is flying in still air with an airspeed of 283  miles per hour. If it is climbing at an angle of 21 °, find the rate at which it is gaining altitude. Round your answer to four decimal places. ​

All edges of a cube are expanding at a rate of 7  centimeters per second. How fast is the volume changing when each edge is 2  centimeters? ​

A petrol car is parked 40 feet from a long warehouse (see figure). The revolving light on top of the car turns at a rate of 30 revolutions per minute. Write  as a function of x. ​ ​

In a free-fall experiment, an object is dropped from a height of 144 feet. A camera on the ground 500 feet from the point of impact records the fall of the object as shown in the figure. Assuming the object is released at time . Find the rate of change of the angle of elevation of the camera when . Round your answer to four decimal places. ​ ​