The answer for "What is petrified wood made of?" would be minerals.
Answer:
The overall climate in the United States of America (USA) is temperate, with notable exceptions. Alaska has an Arctic tundra climate, while Hawaii and South Florida have a tropical climate. The Great Plains are dry, flat and grassy, turning into arid desert in the far West.
Probably minerals because they are definitely in soil
A net population decline resulting from an "excess of deaths over births".
Option: A
<u>Explanation</u>:
Demographic transition is a shift from higher to lower level of fertility and mortality.Rapid development in industrialization and urbanization in 
century resulted into enormous population growth. But decline in early 
century covered many reasons like consequences of two calamitous wars, where Europe suffered large population declination due to battle death and civilian causalities in World War I and II. Hence the acceleration of population growth in 19th century but downfall in 20th is also considered as balance.
