Soil and rocks maybe. not too sure.
The correct answer is: D) H2O… CO2
Redox reactions are reactions of reduction (molecules tend to gain electrons) and oxidation (molecules tend to lose electrons).
Photosynthesis is a set of redox reactions. In photosynthesis electrons are removed from water (H2O) to carbon dioxide CO2 and then used to turn CO2 into organic compounds.
The first step: Oxygen in water is oxidized (light energy required)
The second step: Carbon in CO2 is reduced; sugar is formed (dark reaction).
Independent Variable is what you change in an experiment. A Dependent Variable is what you’re trying to find out. Constants are what you keep that same. Control Group is the standards to which comparisons are made.
The water particle are moving faster which cause the to expand
Answer: D) Pulmonary and aortic valves.
Explanation
There are two main heartbeats from a healthy heart.
The first beat is called the S1 or the lub, and it occurs when the atrioventricular valves (comprising the mitral and tricuspid valves) close.
The second beat is called the S2 or the dub, and it occurs when the semilunar valves (comprising the aortic and pulmonary valves) close.
Listening for heart beats is an essential part of cardiac auscultation.
