Q: What force is greater on rougher surfaces than smooth surfaces? Read this paragraph and choose the correct option from the provided answers: Rougher surfaces have more friction between them than smoother surfaces. That's why we put sand on icy sidewalks and roads. The blades of skates are much smoother than the soles of shoes. That's why you can't slide as far across ice with shoes as you can with skates (see Figure below ). The rougher surface of shoes causes more friction and slows you down. Heavier objects also have more friction because they press together with greater force. Did you ever try to push boxes or furniture across the floor? It's harder to overcome friction between heavier objects and the floor than it is between lighter objects and the floor. Choices: - tension - acceleration - gravity - friction A:
friction

Q: Exchange occurs directly with the external environment in what type of organisms? Read this paragraph and choose the correct option from the provided answers: Choices: - hematopoietic organisms - cell clusters - multicellular organisms - unicellular organisms A:
unicellular organisms

Q: Q: What are kpa, atm, and mmhg measurement units for? Read this paragraph and choose the correct option from the provided answers: The value of , the ideal gas constant, depends on the units chosen for pressure, temperature, and volume in the ideal gas equation. It is necessary to use Kelvin for the temperature and it is conventional to use the SI unit of liters for the volume. However, pressure is commonly measured in one of three units: kPa, atm, or mmHg. Therefore, can have three different values. Choices: - temperature - weight - velocity - pressure A:
A: pressure

Question: Q: The concentration of hydrogen ions in a solution is called? Read this paragraph and choose the correct option from the provided answers: The strength of acids and bases is determined by the concentration of ions they produce when dissolved in water. The concentration of hydrogen ions in a solution is called acidity. It is measured by pH. A neutral substance has a pH of 7. An acid has a pH lower than 7, and a base has a pH greater than 7. Choices: - alkalinity - alcohol - moisture - acidity A:
Answer: acidity

*Question*
Q: The contents of which organ are mixed every 20 seconds? Read this paragraph and choose the correct option from the provided answers: Choices: - the metabolism - pancreas - kidney - the stomach A:
**Answer**
the stomach

*Question*
Q: What effect occurs when a few individuals start, or found, a new population? Read this paragraph and choose the correct option from the provided answers: Founder effect occurs when a few individuals start, or found, a new population. By chance, allele frequencies of the founders may be different from allele frequencies of the population they left. An example is described in the Figure below . Choices: - divergent - convergent - pioneer - founder A:
**Answer**
founder