An airplane takes off from boston for
the 980 km trip to detroit. the plane
lands two hours later. which of the
following best describes the average
speed and direction of the airplane's
flight?
a. 325 km/h w
b. 490 km/h w
c. 980 km/h w
d. 1960 km/h w

The horizontal blue line through the middle of the lens is called the optical axis. as the lamp is moved above or below the axis, keeping the horizontal distance to the center of the lens constant, how does the horizontal distance from the lens to the image change?