A) Halley's comet orbits the sun about every 75 years due to the gravitational force the sun provides. Compare the gravitational force between halley's Comet and the sun when the comet is at aphelion (its greatest distance from the sun) and d is about 4.5 x 10^10 m to the force at perihelion (or closest approach), where d is about 5.0 x 10^10 m. B) In part A, what is the comet's acceleration a) at aphelion? b) at perihelion? (M of the sun=1.99 x 10^30)

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Which lists the main components of darwin’s theory of evolution? a. random mutations drive evolution; the evolution of a population happens slowly; organisms have common ancestors; organisms do not change. b. natural selection drives evolution; the evolution of a population happens slowly; organisms have common ancestors; organisms change over time. c. natural selection drives evolution; the evolution of a population happens rapidly; organisms have common ancestors; organisms change over time. d. random mutations drive evolution; the evolution of a population happens rapidly; organisms have common ancestors; organisms do not change.

1. a net force of 100 newton’s is applied to a wagon for 5 seconds. this causes the wagon to undergo a change in momentum of

Scout feels ill one day before school. her mother puts a thermometer in her mouth and the temperature begins to climb to 100°f. what is happening between the cooler thermometer and scout's body? a) scout's body is applying a force to the particles in the thermometer. b) kinetic energy is being transferred from her mouth to the thermometer. c) potential energy is being lost by the thermometer and gained by scout's body. d) the potential energy stored in foods is converted to mechanical energy to raise the mercury in the thermometer.