I’m stuck can anyone help ! Thanks

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).

The parabola y = x² - 4 opens: a.) up b.) down c.) right d.) left

25 ! the line of best fit is h = 5a + 86. predict the height at age 16.