Why would a cell phone not make a sound in space?

What is the average speed of a car that travels 40mph for 1 hour and 60 mph in another hour will mark brainliest

You are driving directly behind a pickup truck, going at the same speed as the truck. a crate falls from the bed of the truck to the road. (a) will your car hit the crate before the crate hits the road if you neither brake nor swerve? (b) during the fall, is the horizontal speed of the crate more than, less than, or the same as that of the truck?

Explain what it means to view something from a frame of reference. provide an example that illustrates your explanation. (4 points)