Q: What are groups of atoms that behave as a single unit called? Choices: - protons - particles - ions - molecules A:
molecules

(Question)
Q: Billions of what inside the human digestive tract help us digest food, make vitamins and play other important roles? Choices: - neurons - viruses - red blood cells - bacteria A:
(Answer)
bacteria

Ques: Q: Respiratory distress syndrome results from insufficient production of what? Choices: - carbon dioxide - alveoli - lung tissue - pulmonary surfactant A:
Ans: pulmonary surfactant

(Q).
Q: Amplitude describes what about the wave's crest and trough? Choices: - The minimum parts - How frequently the parts occur - The width of the parts - the maximum parts A:
(A).
the maximum parts

Ques:Q: An obstacle or opening that is shorter than the wavelength causes greater diffraction of what? Choices: - tides - ranges - particles - waves A:

Ans:waves

Ques:Q: What travels at a rate of 300,000 kilometers per second, or nearly instantaneously? Choices: - air - sound - gravity - light A:

Ans:
light