Please help me. I'm giving 30 points to the right answer just help, please.

If the value of cos330°is√3/2 then find cos 165°.

You so much whoever answers with accuracy •the parent function of the graph of f(x) is the square root function, which was reflected across the x-axis. which of the following is the equation of f(x)?

$5400 is? invested, part of it at 11? % and part of it at 8? %. for a certain? year, the total yield is ? $522.00. how much was invested at each? rate?