I will give 20 points plz i need help Which causes genetic variations and can result in different alleles?

predation rate

random mutations

competition

environmental changes

What’s the scientific notation for the number 6,840,000,000

Which of the following is true about the products formed during photosynthesis? (5 points) select one: a. they have the same mass as the mass of reactants. b. they are the same set of compounds as the reactants. c. they have more mass than the mass of reactants. d. they are chemically the same as the reactants.

How does a nuclear reactor produce electricity?