# 5. Inside the while loop, check if the input score is within the valid range (0-100). If it's not, display an error message and ask the user to re-enter the score.
# 5a. Check if the input score is within the valid range (0-100).
# - Utilize conditional statements (if, elif, else) to verify the score's validity. Consider how to handle invalid scores.
# - Provide a clear error message to guide the user on what's expected in terms of valid scores.
Ar = (x,y) in R\times R: x2+y2 =r2
Br = (x,y) in R\times R: x2+y2 <=r2
Cr = (x,y) in R\times R: x2+y2 >r2 .
(a) Determine r in I Ar and r in I Ar.
(b) Determine r in I Br and r in I Br.
(c) Determine r in ICr and r in ICr