When a union declares a , workers walk away from their jobs and refuse to return until the issue at hand has been resolved.

Strike

Explanation:

People go on strike by refusing to go to work because of the work environment among other causes that have not been addressed by the employee. Usually used as a last resort to get heard from the employer.

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.'

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