Which of the following is true about a planet orbiting a star in uniform circular
motion?
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a. the velocity vector of the planet points toward the center of the
circle.
b. the speed of the planet is always changing.
c. the velocity of the planet is constant.
d. the acceleration vector of the planet points toward the center of
the circle.

Need asap ‼️ 20 pts which gravitational force field diagram is drawn correctly? (answers in pictures below)

As part of your daily workout, you lie on your back and push with your feet against a platform attached to two stiff springs arranged side by side so that they are parallel to each other. when you push the platform, you compress the springs. you do an amount of work of 79.0 j when you compress the springs a distance of 0.230 m from their uncompressed length. (a) what magnitude of force must you apply to hold the platform in this position? (b)how much additional work must you do to move the platform a distance 0.230 m farther? (c) what maximum force must you apply to move the platform a distance 0.230 m farther?

The mantle is made up of which structural zones?