Answer:
a.
can be made up of a combination of different elements.
Answer:Strontium-90 and cesium-137 have half-lives of about 30 years (half the radioactivity will decay in 30 years). Plutonium-239 has a half-life of 24,000 years. High-level wastes are hazardous because they produce fatal radiation doses during short periods of direct exposure.
Explanation:
Methylation is a process that involves Mercury metal. Methylation is a process by which a methyl groups are added to the DNA molecule. when it occurs it can change the activity of a DNA segment without changing the sequence, additionally, when located in a gene promoter it may act to repress gene transcription.
Answer:
Starting from your own home is the best way to reduce plastic pollution. You can reduce it by stop using plastic bags, water bottles, anything that is plastic. You can reuse things instead. Use less energy. Turn off the lights whenever you leave the house or if you aren't using it. Lastly, conserve water. Don't let the water running if you aren't using it.
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Effective collisions are those that result in a chemical reaction. In order to produce an effective collision, reactant particles must possess some minimum amount of energy. This energy, used to initiate the reaction, is called the activation energy.