What is the closest number of 27. 8 times 9. 6

Find the gradient of f(x,y,z)equals=left parenthesis x squared plus y squared plus z squared right parenthesis superscript negative 1 divided by 2 baseline plus ln left parenthesis x right parenthesis x2+y2+z2−1/2+ln(xyz) at the point left parenthesis negative 2 comma 1 comma negative 2 right parenthesis(−2,1,−2).

Rose bought a new hat when she was on vacation. the following formula describes the percent sales tax rose paid b=t-c/c

Will give a: 122 b: 90 c: 48 d: 180