The metalloid that has three valence electrons is Boron~
Cs -137 has a half life of about 30 years. If 60 years pass, there is two half lives passed so 1/2 * 1/2= 1/4. Take 1/4 and multiply it with the mass given:
(1/4)*20mg=5mg left
In chemistry the law of multiple proportions states that if two elements from more than one compound between them then the ratios of the masses of the second element which combine with a fixed mass of the first element will always be ratios of small whole numbers .
If you want to optimize environmental impact, the ores should be sifted at the site before transporting.
<h3>What is an ore?</h3>
An ore refers to the raw material from which a material is made. Usually, ores are obtained in the raw state from the earth. Metal ores are very important in the manufacturing industry.
In order to reduce the environmental impact of the manufacturing of ores in the metallurgical industry, the ores should be sifted at the site before transporting.
Learn more about environmental impact : brainly.com/question/1023358
Answer:
The answer would be A: satellite and GPS system
Explanation:
This is the answer because you can track someone using the GPS system or you can detect heat on a satelite
