The toxins are the substances which decreases the conc. of oxygen in wzater and increase toxicity
20. The answer is 1 (Precambrian)
21. The answer is 4 (Pennsylvanian)
22. The answer is 2 (Bony Fishes, Dinosaurs, and Mammals)
23. The answer is 2 (Reptiles)
Some students feel distressed only in test situations. They might be said to suffer from Acute Stress.
Answer: Option B
<u>Explanation:</u>
Stress is your body's reaction to specific circumstances. It's abstract, so something that is distressing for you may not be unpleasant for another person. There is a wide range of sorts of stress and not every one of them is terrible. Stress can enable you to act rapidly in a crisis or help you comply with a time constraint.
Acute stress is the most widely recognized sort of pressure. It's your body's prompt response to another test, occasion, or request, and it triggers your battle or flight reaction.
Answer: B) It controls the autonomic nervous system and regulates hunger and thirst sensations.