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
When volcanoes erupt, they emit a mixture of gases and particles into the air. Some of them, such as ash and sulphur dioxide, have a cooling effect, because they (or the substances they cause) reflect sunlight away from the earth. Others, such as CO2, cause warming by adding to the the greenhouse effect.
There is no effect. When you observe a substance's physical properties, you're not doing anything that would catalyze a chemical change. For example, you most often observe with your eyes, and/or, if safe, you waft the substance's smell to your nose. Neither of these observations will effect the substance's physical properties.