36, 99, 9, 123 which does not belong

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).

Polygon hh is a scaled copy of polygon gg using a scale factor of 1/4. polygon h's area is what fraction of polygon g's area?

To decrease an amount by 16% what single multiplier would you use