The answer to this question would be: <span>b.electromagnetic or weak nuclear
</span>
The electromagnetic force can be repulsive or attractive because it was influenced by the magnetic charge. The same charge (positive with positive) will be repulsive but different charge will be attractive(negative and negative). The gravitational force will always be attractive, not repulsive.
Weak nuclear can do both like electromagnetic force.
The answer is B. Asteroids
<span>Cenozoic
</span><span>Mesozoic
</span><span>Paleozoic
</span><span>Precambrian </span>
<span>The RNA world is the hypothesized format of chemical life that existed prior to our current DNA and RNA world. In the RNA world, RNA molecules formed in the primordial soup and began to evolve by self-replication and mutation. This led to increased complexity, natural selection of "better" RNA and diversification of RNA based life.</span>
