The chemical symbol for the element zinc is Zn.
<h3>What is element?</h3>
A chemical element is the one which reacts with other elements to form a compound.
Any chemical symbol must have its first letter written in Uppercase. If the element has two letter chemical symbol, then it should be written in lowercase.
Thus, the student wrote Zn as the chemical symbol of Zinc on the whiteboard.
Learn more about element.
brainly.com/question/13025901
#SPJ1
If you search that click the first link ;)
Answer:
Explanation:
Given
mass of sphere 
diameter of sphere 
radius 

friction will provide resisting torque so
where 







(b)time taken to decrease its rotational speed by 


