Moderate# Extrema Statements

APCALC-RRO1C8

$f( x ) =\cfrac { { x }^{ 5 } }{ 10 } -\cfrac { { x }^{ 4 } }{ 6 } -\cfrac { { 11 }x^{ 3 } }{ 12 } +\cfrac { { 3x }^{ 2 } }{ 2 } +7x-\cfrac { 3 }{ 4 } $

Which of the following is true for the derivative of the above curve?