According to current scientific theory, how did the solar system’s Sun form? A. Hydrogen and Helium collapsed into a ball under electromagnetic forces.
B. Hydrogen and Helium atoms continually collided and stuck together to eventually become the Sun.
C. The supernova of another sun broke off a large chunk of material which became the Sun.
D. Gas and dust from a rotating nebula contracted under gravitational forces.

African penguins, which inhabit the coasts of southern africa, were classified as an endangered species in 2010. two significant threats to their survival are ecosystem damage from oil spills and overfishing by humans. overfishing depletes the food supply of african penguins. the best method to reduce the threat of overfishing would be to . the risk of oil spills could be reduced by increasing the use of , which should oil consumption. if an oil spill does occur, could be used to remove the oil so the ecosystem may more quickly recover.

Reactants undergo chemical reaction to form products. this chemical equation represents one such reaction. the coefficient for one of the reactants or products is incorrect. which part of the chemical equation is incorrect?

How did the club fungi get its name? a. it is named for the club-shaped seeds it produces. b. it is named for the way individual species grow together in small groups called “clubs.” c. it is named for the club-shaped area where it produces spores. d. it is named for the club-like mechanism it uses to kill its prey.