Answer:
Ocean-Continent Convergent Plate Boundaries
Did you perhaps mean the phase of matter?
If so, then a solution has only one phase of matter: liquid. It is always almost always liquid because solutions are made up of a solvent and a solute and a solvent is always a liquid. Though, some may come in an emulsion form, but still it can be considered as liquid
Answer is: <span>a. two 511 kEv photons are formed.
</span><span>When the positrons reach thermal energies, they start to interact with electrons by annihilation.</span>
Positron-emission tomography<span> (</span>PET)<span> is a </span>nuclear medicine functional imaging<span> technique that is used to observe metabolic processes in the body. The system detects pairs of </span>gamma rays<span> emitted indirectly by a </span>positron<span>-emitting </span>radionuclide.
The catalytic converter of a secondary air injection system converts the hydrocarbons and carbon monoxide to carbon dioxide (CO2) and water (H2O). It is a fundamental part of a vehicle.
<h3>Catalytic converter and air injection systems</h3>
A catalytic converter refers to the device observed in a car and/or vehicle, which is used to remove different contaminant gases.
In general, the catalytic converter is placed close to the car engine and reduces the release of hydrocarbons.
In general, the air injection system is connected to the catalytic converter in order to provide useful oxygen required for oxidation reactions.
Learn more about catalytic converters here:
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