Ammonoids are good as index fossils because of the following characteristics;
<span>1.
</span>Their abundance and vast distribution across most shallow
marine waters during the periods
<span>2.
</span>They have easily recognizable
features, such as shells and the highly crenulated and complex suture, that are well preserved in rocks
<span>3.
</span>Their rapid
evolution that can assist determine changes and variations in the then environment
That process is known as "Ovulation"
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Answer;
-The third stage fever
Explanation;
-Fever, also referred to as pyrexia and febrile response, involves having a temperature above the normal range (above 37.5 or 38.3 °C) due to an increase in the body's temperature set-point (36.5–37.5 °C). This increase in set-point temperature triggers increased muscle contractions and causes a feeling of cold.
-The first stage of a fever is marked by headache and body aches, the second stage is marked by the chills, and the third stage is the flush state. The fourth stage is defervescence.
The three grains are rice, wheat, and corn
Rice is the main grain used in places such as Asia ans SEA, corn is mostly used in the Americas, while wheat is mostly found in European countries.