What letter do i need if i worked under the table for proof of hardship and loss of income.

you can lose ranking 2 ways.

1) you don't have enough points due to you expending them by asking questions/your answers are deleted.

2) your brainliest's expired. this means that brainliests, once they exceed the 30 day limit, expires. this is to ensure that you continue to contribute into the community at a constant rank if you want to continue to have/exceed the rank you have right now.

if you go to profile, and click "show more information" located on the bottom left of the box with your information (on top of the questions answered, questions asked, and friends), you will be given the following information (example):

member since : 02/13/2017, 18: 11

questions answered: 9741

questions asked: 162

no. of brainliest answers: 1575

brainliest answers in last 30 days: 10

warnings: 0 view

questions/answers reported: 2637

questions/answers incorrectly reported: 64

look at the "brainliest answers in the last 30 days". this is the one that will affect your rank other than your points. again, once your brainliest expires (was earned 31+ days ago), it will not be counted.

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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.'