Consider the following:
A foreign automobile company builds a manufacturing plant in Tennessee and European investors buy U. S. Treasury Bonds.

a. Both activities would be considered direct investment.
b. Both activities would be considered portfolio investment.
c. The auto manufacturer in engaging in portfolio investment, and the European investors are engaged in direct investing.
d. The auto manufacturer in engaging in direct investment, and the European investors are engaged in portfolio investing.

both activities would consider direct investment

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ans.

heterothermic organisms include those organisms that can switch between homeothermic (having body temperature higher than environment) and poikilothermic (having variation in internal body temperature) strategies.

some migratory birds show heterothermy as they decrease their metabolic rate during cold nights to keep their body temperature low. drop in metabolic rate allows increase in production efficiency of birds that reduces the internal body temperature to make it equal to external cold temperature during cold nights.

thus, the correct answer is 'birds allow their temperature drop in order to increase their production efficiency.'