How will the level of carbon in the atmosphere change if humans do nothing to reduce their impact on the carbon cycle?
carbon will be removed from the atmosphere altogether.
the level of carbon in the atmosphere will decrease.
carbon in the atmosphere will remain the same.
the level of carbon in the atmosphere will increase.

Option (4)

Explanation:

Carbon forms the basin element for the existence of life. It is present in the atmosphere in the form of CO₂, which is one of the major green house gas. It plays an important role in the carbon cycle.

The increase in the concentration of carbon in the atmosphere can lead to the global rise in the temperature. It can lead to global warming. The amount of carbon in the atmosphere has been rising continuously, right after the industrial revolution.

The carbon is mainly emitted from the heavy industries and factories, vehicles, burning up of fossil fuels. It also increased due to the increasing absorption of solar radiation.

This emission of carbon if not controlled by the humans, then the concentration of carbon in the atmosphere will abruptly increase after some decades.

Thus, the correct answer is option (4).

spiders belong to a group of arachnids.

arachnids have the following traits :

they have two body parts.

they have eight legs unlike insects which have 6 legs.

they have no wings.

these traits distinguish them from insects.

the information that antonio is doubting us the statement that spiders differences are as a result of being first to evolve.

this is because the evolution of one species is independent of the other species.