Tutor profile: Andrew W.
Subject: Linear Algebra
What are some useful uses of a matrix?
Matrices can be used to represent systems of equations, linear transformations, or even functions.
Subject: Basic Chemistry
What makes up an atom?
An atom is composed of 3 separate building blocks, known as subatomic particles. These particles are the proton, neutron, and electron. Atoms are composed of a nucleus, a very compact and heavy core composed of protons and neutrons mushed together. This nucleus is positively charged, because it is made of protons (a positively charged particle) and neutrons (a particle with no charge). An atom's nucleus is surrounded by an electron cloud, composed of light, fast moving electrons.
Describe the process of natural selection, and how it ultimately leads to evolution.
Natural selection is actually a pretty easy concept to grasp. In any given environment an organism or group of organisms lives in, there are a set of selective pressures that influence who survives and reproduces, and who dies and fails to pass on their genetic code. For example, humans or other animals with strong legs will be able to run faster, allowing them to more easily track down prey and run away from predators. Organisms with more favorable traits will have a larger chance of passing on their genes to the next generation; over millions of years, unfavorable genes will be erased from the genome and favorable genes will be selected for. This process is known as evolution
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