HEY DEAR..
The particles of light known as photon.
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C5H10O5 would weight a total of 2.312 kilograms.
Gamma radiation have the most penetrating power. It can penetrate through human body, aluminum and other metals. It can be stopped by lead. Hence, the radioactive waste are stored in lead container for safety purposes. The beta ray has more penetrating power than the alpha but less than gamma. The beta radiations can be stopped by aluminum. The alpha radiations have least penetrating power and it can be stopped by human hands.
I would say B because c and d would decrease competition and a would do the same, or just kill the ecosystem.
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