Answer:
(D) a brief early period of hyper rapid expansion of space-time.
Explanation:
Cosmic inflation is a theory which states that in an interval of 10⁻³⁶ seconds to around 10⁻³³ seconds after the big bang there was a massive expansion.
According to the big bang theory the universe came to be from a singularity i.e., a point of infinite gravitational field. The universe is expanding this means that according to the conservation of energy the universe was expanding from the beginning.
Answer:
-0.912 m/s
Explanation:
When the package is thrown out, momentum is conserved. The total momentum after is the same as the total momentum before, which is 0, since the boat was initially at rest.

where
are the mass of the child, the boat and the package, respectively.
are the velocity of the package and the boat after throwing.



In exothermic reactions, heat and light are released to the surrounding environment. On the other hand, in an endothermic reaction, heat is required and therefore it can be considered as a reactant.
- In exothermic reactions, light and heat are released into the environment (Option D).
- Exothermic reactions release energy in the form of heat or light.
- Combustion reactions are generally exothermic reactions.
- After an exothermic reaction takes place it is possible to observe that the energy of the products of the reaction is lesser than the energy of the reactants.
- The energy released in exothermic reactions is evidenced by the increase in temperature of the reaction.
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