Answer:
0.3656 :)
Step-by-step explanation:
We can convert 20km to 20,000m. Then, we can subtract 800m (walking distance) from 20,000m which would result in 19,200m. Then we can put 19,200m and 20,000m as a fraction (19200/20000). Before we can multiply it by 100 to make it in the percentage form, we can get rid of 2 zeroes for both number making it 192/200 and then further simplifying it to 24/25 by dividing both numbers by 8. Finally to get the percentage we can multiply 24 and 100 (2400) and then divide the result (2400) by 25. The final answer is 2400/25=96 meaning he cycled 96% of the journey and walked 4% of the journey (100-96=4).
A gamma ray by definition, has a zero charge and a zero mass.
So when it is released it does not change the mass or nuclear charge of the parent material.
But it does involve the release of energy like all radioactive processes.
So the statement is True.