In 1986, several robotic spacecrafts were sent into space to study the halley's comet. which of these statements best explains why humans should continue to send robotic spacecrafts into space? a. they absorb harmful radiations in space. b. they change weather conditions on earth. c. they discard some myths about objects in space. d. they destroy meteors and comets which might strike earth.

The electric potential v is constant everywhere within a certain region of space. which statement below is true? the choices are: the electric field is also constant (but not zero) within the region. a charged particle placed within the region will experience an electric force. the electric field is zero everywhere within the region. the electric field varies from place to place within the region.