Achemical equation is balanced by changing or adding
a.
chemical symbols.
c.
numbers in front of molecules.
b.
subscripts after atoms.
d.
reactants in the product.

Which object forms when a supergiant runs out of fuel? a red giant a black hole a white dwarf a neutron star

Which of the following happens during cell division? (a) energy is created (b) waste is eliminated (c) carbon dioxide is released (d) damaged cells are replaced

Observation and experimentation have led many scientists to accept a theory about the origin of the universe. this theory is called the big bang theory. scientific evidence collected and observed by scientists around the world suggests that the universe is ever expanding from a hot and dense initial state. what makes this a scientific theory? (2 points)