No spacecraft has been built yet that was able to absorb harmful
radiations in space, change weather conditions on Earth, or destroy
meteors and comets which might strike Earth.
We should continue to send robotic spacecrafts into space
because they help discard some myths about objects in space.
In other words, they help us learn things that we never knew before.
Answer B is the correct pair.
Answer:48.2 Joules
Explanation:
Given
two masses of 0.2 kg and 0.4 kg collide with each other
after collision 0.2 kg deflect 30 north of east and 0.4 kg deflects 53.1 south of east
Velocity of 0.2 kg mass is
Velocity of 0.4 kg mass
Thus total Kinetic energy 
Kinetic energy=48.2 J
Answer:
The correct answer is theory of general relativity.
Explanation:
According to the statement of equivalence the gravitational mass force on an object standing on the surface of earth is same as the pseudo force that acts on it if it accelerated at acceleration equal to acceleration due to gravity.
According to Einestine both the forces are indistinguishable as both the forces produce same effects. Thus both are equivalent and thus gravity is a phenomenon that can be analysed in a radically different way which gives some strange results such as bending of light, existence of black holes,e.t.c
