Answer:
B
Explanation:
"I think my bike is making a scraping noise because the bearings are not lubricated."
D. It gives the same results when experiments are repeated
Explanation:
For example, Identify the number and type of ions formed in a reaction of calcium and carbon. Step 1: Determine the number of valence electrons for each element and whether the element loses or gains electrons. Calcium has 2 valence electrons and is a metal so it will give up two electrons.
