By radical do you mean the square root symbol?
Answer: 
Step-by-step explanation:
You want to isolate s which means get it by itself. So all you gotta do is divide both sides by t
Answer:
1/2
Step-by-step explanation:
First create like dominators
2/3 -1/6 = 4/6 - 1/6
simplify using subtraction
4/6 - 1/6 = 3/6
Simplify the answer
3/6 = 1/2