Find the difference: 5/6 - 3/12 = ?

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?

Parallelogram rstu is a rhombus. m∠r = 120° what is m∠t = 120 (what is m∠rsu? )