Mrs. wu was primarily a homemaker and employed in jobs that provided taxable income only sporadically. her husband worked full-time throughout his long career. she has heard that to qualify for medicare part a she has to have worked and paid medicare taxes for a sufficient time. what should you tell her?

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.'