Answer:
A. Yes, the substance must be water.
Explanation:
The density of a substance is unique to it. Density is defined the as the amount of substance contained per volume.
One of the ways of identifying a substance is to determine its density. Every matter is known to have their own specific densities. This makes them different from other substances. The density of gold is unique to it and it differs from that of silver.
In fact, water has density of 1.00gcm⁻³. Experimental errors and some little factors must have altered our expected figure. This a case of precision and accuracy in the experiment.
Answer:
They are produced from rocks (parent material) through the processes of weathering and natural erosion.
Explanation:
Soil minerals form the basis of soil. They are produced from rocks (parent material) through the processes of weathering and natural erosion. Water, wind, temperature change, gravity, chemical interaction, living organisms and pressure differences all help break down parent material.
Answer:
a)


b)
Sulphurdioxide
c)


d)
Incomplete combustion produce harmful gases.
Explanation:
a)
Carbon reacts with atmospheric oxygen to form carbondioxide as well as sulphur dioxide.
The chemical equations are as follows.


b)
Sulfur dioxide is very harmful to the environment to cause acid rains.
This harmful gas mix with rain water to form sulphuric acid.
c)
The balanced chemical equation for the reaction that produces harmful environmental effects is as follows.



d)
In the absence of proper amount of oxygen required for combustion, incomplete combustion will take place which will result in formation of more carbondioxide an other harmful gases.
Answer:
B. is coupled to the production of ATP
Explanation:
The magnesium in chlorophyll acts as an activator of enzymes associated with energy metabolism, especially respiratory enzymes and others that act on phosphorylated substrates such as ATP.
Independent variable: calculators, computers
Dependent variable: speed
3 constants: seat, atmospheric condition, and time.
Control: none
<h3>What are variables</h3>
Variables are of different types in experiments. They can be:
- Independent: a variable that is supplied by the researcher and which can be tweaked among different experimental groups to produce different outcomes.
- Dependent: variables whose value is dependent on the kind of independent variable supplied by the researcher. It is the actual variable that is measured during the course of experiments.
- Constant: all other variables that are kept the same among experimental groups.
Thus, in this case, the independent variable will be the calculator or computer/calculator combination given to the two groups.
The dependent variable will be the speed at which each group finished solving the math problems.
The constant variable will be all other variables supplied to the two groups.
More on variables can be found here: brainly.com/question/20725701
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