Answer the following question given this paragraph: Solution 1. Saltwater acts as if it were a single substance even though it contains two substancessalt and water. Saltwater is a homogeneous mixture, or a solution. Soil is composed of small pieces of a variety of materials, so it is a heterogeneous mixture. Water is a substance; more specifically, because water is composed of hydrogen and oxygen, it is a compound. Oxygen, a substance, is an element. Q: Saltwater is a homogeneous mixture, another term for what? Choices: - structure - element - lipid - solution A:
solution
(Question)
Answer the following question given this paragraph: Did you ever watch a relay race? After the first runner races, he or she passes the baton to the next runner, who takes over. Neurons are a little like relay runners. Instead of a baton, they pass neurotransmitters to the next neuron. Examples of neurotransmitters are chemicals such as serotonin, dopamine, and adrenaline. Q: What do neurons pass to the next neuron? Choices: - contaminants - blood - receptors - neurotransmitters A:
(Answer)
neurotransmitters
Ques: Answer the following question given this paragraph: Q: When the number of active receptors falls below that threshold, what happens to the cellular response? Choices: - it responds - it increases - it stabilizes - it ceases A:
Ans: it ceases
(Q).
Answer the following question given this paragraph: When matter reacts, there can be mass that comes from nowhere and is unaccounted for. Q: When matter reacts, there can be what that comes from nowhere and is unaccounted for? Choices: - concentrations - combustions - bonds - mass A:
(A).
mass
Ques:Answer the following question given this paragraph: Animals and some bacteria and fungi carry out lactic acid fermentation. Lactic acid is a waste product of this process. Our muscles perform lactic acid fermentation during strenuous exercise, since oxygen cannot be delivered to the muscles quickly enough. The buildup of lactic acid is believed to make your muscles sore after exercise. Bacteria that produce lactic acid are used to make cheese and yogurt. The lactic acid causes the proteins in milk to thicken. Lactic acid also causes tooth decay, because bacteria use the sugars in your mouth for energy. Q: During strenuous exercise our muscles perform what kind of fermentation? Choices: - nitric acid - residual acid - excessive acid - lactic acid A:

Ans:lactic acid
Question: Answer the following question given this paragraph: The experiment is a cornerstone in the scientific approach to gaining deeper knowledge about the natural world. Scientists use the principles of their hypothesis to make predictions, and then test them to see if their predictions are to be confirmed or rejected. Q: Scientists use the principles of what to make predictions, which they then test? Choices: - their teachers - their guesses - their faith - their hypothesis A:
Answer:
their hypothesis