If hIV causes the immune system to not work properly, then what causes the immune system to not work properly? Answer choices: - HIV - lack - DDT - p53 - antibiotics - h2o - memory cells - HPV
HIV

If amutation in cells usually occur in genes that control the cell cycle, then what usually occur in genes that control the cell cycle? Answer choices: - Leptospirosis - competition - A Greek letter - a mutation in cells - Plant reproduction - biological diversity - resistance - resistance activities
a mutation in cells

If hitting an object causes frequency waves, then what does hitting an object cause? Answer choices: - frequency waves - harmful substances - Electrical energy - chemical reaction - friction - Movement - heat energy - chemical changes
frequency waves