If a country's saving rate increases, then in the long run a. productivity and real GDP per person are both higher. b. productivity is higher but real GDP per person is not higher. c. real GDP per person is higher but productivity is not higher. d. neither productivity nor real GDP per person is higher.

A) productivity and real GDP per person are both higher.

Explanation:

In the long run, an increase in savings will increase total investment. If total investment increases, then the productive capacity (productivity) and the aggregate supply should also increase. An increase in investment is the best way to guarantee a sustainable increase in aggregate demand without increasing the inflation rate.

When productivity increases, the real GDP per capita also increases.

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.'

the first one $24,630