HELP QUICKLY THIS IS FOR MY TEST

Write a polynomial function f of least degree that has rational coefficients, a leading coefficient of 1, and the given zeros. 3, 4+2i, 1+(sqrt)7 the answer is supposed to be: f(x)=x(^5)-13x(^4)+60x(^3)-82x(^2)-144x+360 what am i doing wrong?

The standard deviation for a set of data is 5.5. the mean is 265. what is the margin of error?

Idon't get undoing if its pass adding and subtracting so can someone ? x-2 over 5 = 18