Where would the "OR" go in the following function:

Cell A1 can be Yes or No
Cell A2 can be any number
Cell A3 can be any number

If EITHER Cell A1 is "Yes" OR Cell A2 is equal to or above 50 AND Cell A3 is
equal to or above 100, then return "OK";
however, if cell A1 is "No" AND either A2 is below 50 or A3 is below 100,
then return "No good"

=IF(AND(A2=50,A3=100),"OK","No good")

How would I add the OR term to test whether A1 is Yes or No?
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MZ