Answer:
I think balanced
Explanation:
because there is a 2 on each arrow
Answer:
you have probably missed some details in the question.
Answer: Lever
A wheelbarrow consists of a lever to be able to lift the material, and a wheel to be able to move it horizontally. So in a sense, a wheelbarrow is a complex machine consisting of two simple machines.
Mold
Explanation:
A mold is a cavity that is left behind in the rock after an organism hard part has been dissolved. These are important fossils that useful in relative dating.
- Some hard parts of organism are preserved in form of molds in soft sediments.
- The outline and important details of the hard part is preserved when the mold dissolves away.
- Fossil molds are representative on the internal outline of the hard parts of organisms.
- They are usually recognized as a part of body fossil in a section.
learn more:
Fossils brainly.com/question/7382392
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Answer:
electrons exist in specified energy levels
Explanation:
In its gold-foil scattering with alpha particles, Rutherford proved that the plum-pudding model of the atom theorised by Thomson was wrong.
From his experiment, Rutherford inferred that the atom actually consists of a very small nucleus, where all the positive charge is concentrated, and the rest of the atom is basically empty, with the electrons (negatively charged) orbiting around the nucleus at very large distance.
However, Rutherford did not specify anything about the orbits of the electrons. Later, Bohr predicted that the electrons actually orbit the nucleus in specific orbits, each orbit corresponding to a specific energy level. Bohr's model found confirmation in the observation of the emission spectrum lines: when an electron in one of the higher energy level jumps down into an orbit with lower energy, the atom emits a photon which has an energy exactly equal to the difference in energy between the two orbits (and this energy of the photon corresponds to a precise wavelength).
