Final answer:
A biconditional statement for 'If an angle is acute, then it measures less than 90 degrees' is 'An angle is acute if and only if it measures less than 90 degrees.'
Step-by-step explanation:
The biconditional of the statement "If an angle is acute, then it measures less than 90 degrees" is "An angle is acute if and only if it measures less than 90 degrees." This biconditional statement indicates that for an angle to be considered acute, it must measure less than 90 degrees, and conversely, if an angle measures less than 90 degrees, then it must be an acute angle.