On the way home from school, you stop at a stoplight. Suddenly you hear the siren of an ambulance in the distance. As you turn, you see the approaching vehicle so you wait patiently as the ambulance eventually speeds through the intersection. Describe the sound you hear throughout this process. Explain
your answer in terms of the Doppler Effect.

find the surface area of the sphere to the nearest square unit. use a calculator.

a. 254 in.2

b. 64 in.2

c. 127 in.2

d. 1,018 in.2

earth's neighboring galaxy, the andromeda galaxy, is a distance of 2.54×107 light-years from earth. if the lifetime of a human is taken to be 70.0 years, a spaceship would need to achieve some minimum speed min to deliver a living human being to this galaxy.