Some agree its in the billions range somewhere close to 3 billion.
I believe the answer to this one is (A) Single Gene Traits. I searched it up and it says “Widow’s peak occurs when the hairline forms a distinct point in the center of the forehead. Widow’s peak is controlled by a dominant allele (W).”
Answer: The Magdeburg hemispheres are a pair of large copper hemispheres, with mating rims. They were used to demonstrate the power of atmospheric pressure. When the rims were sealed with grease and the air was pumped out, the sphere contained a vacuum and could not be pulled apart by teams of horses.
Explanation:
Answer:
Hydrogen sulfide or methane
They use methane as an energy source