HEY HELP WHATS THE WIDTH OF 25 SQUARE CENTIMETERS AND 5 CENTIMETERS

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).

If f(x)= 3x+6 which of the following is the inverse of f(x)

Average acceleration: i have no idea how to do this.