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.

3. a worker pushes a 30.5 kg polished stone along a polished table with a force on bonin a straight line for 5.20 s after starting from rest. there is no friction between thestone and the table. at the end of the table. the stone is hooked to a cable with a lengthof 62.0 cm to rotate it to a rough table to store until they can be picked up. the roughtable has a coefficient of static friction 0.702 with the polished stone. remember that 8= 9.80 m/s2a) what is the speed of the stone when it is hooked to the cable? b) what is the tension in the cable while the stone is rotating? (there is still nofriction)c) how much force is needed to make the stone begin sliding from rest on therough table? ius = 0.70262.0 cm30.5 kg20.5 kg6= 0

What type of force holds atoms together in a crystal?

Did anyone do 1.06 lab: cloud formation i need with it i go to k12 lavcame i need to get it done quick