Cause(s) populations to change over time.

natural disasters
natural selection
weather
genes

Describe two recent or ongoing space missions.

Which of these statements is false? a. others may notice a problem with a relationship before the people involved. b. the first sign of a problem with a relationship is a feeling of anger. c. damaged relationships can be repaired. d. even good relationships can be damaged.

Which best describes the nucleus of an atom a. it is where all of the particle s of the atom are located b. it is the negatively charged part of the atom c. it is where the electrons and the protons are located d. it is the part of the atom with the greatest mass