B is the answer! Because no one would be pushing the rock all the way down the hill it would just go down by itself by rolling!!
Hope i helped plz mark as brainlist and 5 star'!
1. Proton
2. negative ion
3. electric charge
4. electron
5. repel
6. attract
7. positive ion
Space is more hostile to the human body.
The product of the dosage Gy and relative biological efficiency yields a radiation dose equivalent Sv (RBE).
Sv =dose in Gy * RBE Sv=dose in GyRBE
The quantity of ionising energy absorbed by 1 text kg1 kg of tissue is defined as a radiation dose Gy. While RBE is a measure of a specific dose's biological effect relative to the biological effect of an equal quantity of X rays.
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What is radiation?</h3>
Radiation is energy that moves through space at the speed of light from a source. This energy is coupled with an electric and magnetic field, and it exhibits wave-like qualities. Radiation is sometimes known as "electromagnetic waves."
Nature has a diverse variety of electromagnetic radiation. One example is visible light.
X-rays and gamma rays are extremely energetic. They may take electrons from atoms when they engage with them, causing the atom to become ionised.
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