Explanation:
Knowing the number of valence electrons in one of the alien elements helps in identifying it because the number of valence electrons can help categorize the alien element. Similar elements have the same valence electrons and knowing the category of the element can help further analyze the element.
Answer:
Curd, lemon juice, orange juice and vinegar taste sour. These substances taste sour because they contain acids. The chemical nature of such substances is acidic. The word acid comes from the Latin word acere which means sour.
Answer:

Explanation:
Given
The data in the table
Required
Follow the steps appended to the question;
Step 1: Calculate the Mean or Average
Mean = Summation of lengths divided by number of teams;



Step 2: Get The Range



Step 3: Divide Range by 2



Step 4: Determine the Precision

Substitute 2.70 for Average and 0.1 for Approximate Range

I think that is called a Metamorphic rock.