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.
Buffer is formed from weak acid and its salt with strong base (conjugate base) so the correct answer will be 0.1 M HCN and 0.1 M LiCN and all other choices are incorrect
Answer:
The "pressure gradient" causes the movement of air from high-pressure areas to low-pressure areas.
Explanation:
The pressure gradient is the physical entity which tells us about the direction of the air in which it will move. It also tells us about the rate at which it will increase as well as decrease in the specific location. The unit of the pressure gradient used is pascals per metre. The difference of this quantity creates uneven increase in the temperature of the surface of the Earth, only when the solar radiation focuses over the equator. They are also the reason behind the beginning movement of the air.