The correct answer is<span> a. Volcanic glass
Volcanic glass is also known as Obsidian. It is formed when lava cools down too rapidly and crystals grow minimally, without grains.</span>
It takes 27 days for the moon to orbit the earth
Carbon dioxide (chemical formula <span>CO2</span>) is a colorless and odorless gas vital to life on Earth. This naturally occurring chemical compound is composed of a carbon atom covalently double bonded to two OXYGEN ATOM
Prokaryotic And Eukaryotic :)
The answer is 'instinct'. This is innate complex behavior exhibited by an organism that is not learned. Some common examples are dogs shaking themselves dry when wet, honeybee communication via intricate dances, animal courtship behavior during mating season and the building of nests by birds.