Evaluate the expression 1/the square root of -1

does this equal -i ?

Evaluate the expression 4/3 – the square root of -4

only thing i can come up with is 4/3-2i but that is incorrect…

Factor the polynomial 256x^4 – 25 find all the zeros.

it is +/- square root of 5/4 but is it +/- i square root of 5/4 or 5/2 ?

Find all zeros of the polynomial P(x)= x^5 + x^3, including their multiplicities. Also determine where the graph of the polynomial crosses/touches the x-axis

and finally

Find the polynomial of degree 5, with integer coefficients that has zeros of -1. 2, i, with 2 being a zero of multiplicity 2 <-- that part confuses me...