Answer:
The answer is C)
Explanation:
The predators were unable to keep the population of the mussels down. The mussels took more area of the rock. Other species that needed space did not return to the tidal pool. Otters can also be keystone species as they eat urchins. By doing so, they prevent the sea urchins form eating all the kelp plants and removing the entire habitat for many other species. The Keystone Species theory shows that this impact of few predators, that made up a minor amount of the total species, could have such a high impact on the ecosystem.
Answer:true
Explanation: Seventy-five percent of Canada's population resides in a narrow 150-kilometre band pushing up against the U.S., with close ties south of the line.
Answer:
The current amount of the Potassium-40 sample is approximately 37.521 grams.
Explanation:
The amount of the sample of the radioactive isotope decays exponentially in time, the amount of mass of the sample as a function of time (
), in grams, is described below:
(1)
Where:
- Initial mass, in grams.
- Time, in years.
- Time constant, in years.
The time constant can be found from half life (
), in years, described in statement:
(2)
If we know that
,
and
, then the current amount of the sample is:




The current amount of the Potassium-40 sample is approximately 37.521 grams.
Answer: A) import substitution.
Explanation:
Import substitution is the process of replacing items sourced solely from other countries with domestic production/industries. It reduces or eliminates the reliance on importation and is usually put in place for key products.
It is also practiced by developing countries or economies as a policy to reduce dependency on other countries, as well as limit the effects of foreign trade on the foreign exchange market.