Is each biconditional statement true or false? select true or false for each statement a angle is a right angle if and only if the measure of the angle is 90 degrees an angle measures 120 degrees if and only if the angle is an obtuse angle an angle measures 180 degrees if and only if the angle is a straight angle

i think all three statements are true because the definition of a right angle is an angle that is 90º, and 12º means that its an obtuse angle bc its greater than 90º, and a straight angle is 180º

a complex number is a number that can be expressed in the form a + bi, where a and b are real numbers, and i is a solution of the equation x2 = −1. because no real number satisfies this equation, i is called an imaginary number. has no real solution, since the square of a real number cannot be negative.