Answer:
Geologists use the following tests to distinguish minerals and the rocks they make: hardness, color, streak, luster, cleavage and chemical reaction. A scratch test developed by a German mineralogist Friedrich Mohs in 1822 is used to determine mineral hardness.
The answer is 2.25 hours, or 2 hours and 25 minutes.
9.50-5=4.50
4.50/2=2.25
The classification of each of the elements into nonessential element, essential bulk element, or essential trace element are as follows:
Nonessential elements:
Essential bulk elements:
- Carbon,
- Nitrogen,
- Calcium,
- Hydrogen
Essential trace elements:
The complete question
The elements are: Hydrogen, iron, Copper, Nitrogen, Helium, Carbon, Aluminum, Calcium, Argon
<h3>What is Essential and Nonessential Elements?</h3>
Nonessential elements as the name implies are elements which are not necessary for the functional routine of the body and hence are not included in diets.
Essential bulk elements are elements which are needed for the proper functioning of the body and hence are required in relatively large amounts.
Essential trace elements are required in minute quantities in the body.
Learn more about Essential and nonessential elements;brainly.com/question/861262
Answer:
D. Comets spend most of their time far from the Sun.
