The PARC Company makes whatsits and in order to make whatsits, they must have gismoes. PARC can purchase gismoes to be used in building whatsits for $90 each. PARC can manufacture their own gismoes for $7000 per year overhead cost plus $25 direct cost for each gismoe, provided they purchase a gismoe maker for $100,000. PARC expects to make whatsits using gismoes for 10 years. The gismoe maker should have a salvage value of $20,000 after 10 years. PARC uses 12% as its minimum attractive rate of return. At what annual production rate should PARC make their own gismoes

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.'