Answer:
The patent limits the sharing of important scientific knowledge.
Explanation:
A.
mitochondria
B.
vacuole
C.
Golgi body
D.
nucleus
ASAP
Answer:
Explanation:
There are two major types of mixtures; homogeneous and heterogeneous mixtures.
Homogeneous mixture is a mixture in which its constituent particles are evenly distributed throughout the mixture. Examples are steel, bronze and air (as stated in the question). While heterogeneous mixture is a mixture in which it's constituent particles are not evenly distributed throughout the mixture. Example includes sand and water solution.
Salt water is an homogeneous mixture because the percentage of salt in a sample of salt from a particular mixture is the same in every other sample (of the same volume) of the same mixture.
From the above, we can deduce that air is an homogeneous mixture because a sample of air (in a particular area) will contain the same constituent by proportion as another sample of air (in the same area). This means that the percentage of oxygen, nitrogen, carbon dioxide, water vapour, argon and other substances in one sample of the air will be equal to the percentage of this constituents in the other sample of the air.
Same can be said about steel and bronze. For steel, each gram of the same steel will contain the same percentage of carbon and iron. And also, each gram of the same bronze will contain the same percentage of copper, tin and other metals present.
For better understanding, let's consider an heterogeneous mixture. A mixture of sand and water solution cannot have the same proportion throughout, this is because sand particles in some samples (of a particular volume) of a particular mixture will be different from sand particles in some other samples (of the same volume) of the same mixture.
toothpaste in reducing
cavities?
How does the daytime
• temperature affect the
formation of dew at night?
Which is a better absorber
of heat, an object painted
black or the same object
painted white?
Can plants prepare food
even in artificial light?
Why does a rolling ball slow
down as it moves?
Answer:
Following questions are better answered by observational study:
- How does the daytime temperature affect the formation of dew at night?
- How effective is a new toothpaste in reducing cavities?
Following questions are better answered by controlled experiment:
- Which is a better absorber of heat, an object painted black or the same object painted white?
- Why does a rolling ball slow down as it moves?
- Can plants prepare food even in artificial light?
Explanation:
An observational study is one in which the researcher doesn't manipulate anything.
In a controlled experiment, the researcher manipulate the outcome of the experiment and controls the factors that might affect the experiment to see different results in different conditions.
So, for questions over which research do not have any control, mostly natural processes, observational study is a better option.
However, to check why a rolling ball slow down, controlled experiments are done to find out all the factors.
Plants placed in artificial light is also an controlled experiment as the researcher will himself place the plants in artificial light and keep them away from natural light.
Similarly, to check if color of the object affects the amount of heat absorbed by that object, a controlled experiment must be performed. Same object should be painted white and observed and then painted black and observed.