Answer:
Calcium is a metal.
Explanation:
It is considered a metal because it is most likely to give away it's two valence electrons to reach Argon. All the elements in gray are metals.
they are both types of passive transport which means they require no energy. They both work with the concentration gradient which means they go from a high concentration area to a low concentration area. The differences are simple diffusion just goes though the membrane of a cell while facilitated diffusion uses a protein channel
Simple diffusion: it is the process where molecules move from a area of high concentration to an are of lower concentration. There is no energy needed in simple diffusion. For example when sodium is highly concentration in a cell, it moves outside of the cell where sodium is less concentration. it takes no energy as simple diffusion is random and molecules move according to their concentration.
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Answer:
The planets follow these orbit paths as they travel around the Sun. The Sun’s gravity
makes the planets move in this way. It pulls on the planets, keeping them in motion in their orbit.
Modeling is a way to see ideas or have a particular idea or
concept.
Models do have some lines .
Often a model is made with certain things.
A model of the solar system may contain all of the planets and the Sun, but it may not include the planets’
individual moons or every planit and rock in the solar system.
Explanation: if you think about it and and look at pics it is easy
hope this helps
1 meter = .001 kilometers so 4.5 x 10^3 = 4500 so .001 x 4500 = 4.5 kilo