Answer only the last question where it says (why can no angel)

Because three points of the angle have to be named ex; angle ABC

4should be the last one n=4

Answer to your question: a. the fundamental theorem of algebra tells you that the equation will have two complex roots since the degree of the polynomial is 2. the roots are ​ x=1±i7√2 .number of roots=degree of polynomialhere, degree of polynomial is 2 so number of roots will be 2.hope it *_*