I need the answers and the steps please

Acompany is testing in comparing to lightbulb designs the box plot shows the number of hours that each lightbulb design last before burning out which statement is best supported by the information of the plot

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).

Evaluate-27 ^4/3/8 a) - 81/16 b) 81/16 c) 16/81