Find the Slope of the Graph of the Function at the Given

Multiple Choice

Find the slope of the graph of the function at the given value. $f ( x ) = \frac { - 5 } { x ^ { 3 } }$ when $x = 9$

A) $f ^ { t } ( 9 ) = - \frac { 5 } { 2187 }$
B) $f ^ {t } ( 9 ) = - \frac { 5 } { 729 }$
C) $f ^ { t } ( 9 ) = \frac { 5 } { 27 }$
D) $f ^ { t } ( 9 ) = - \frac { 5 } { 27 }$
E) $f ^ { t } ( 9 ) = \frac { 5 } { 2187 }$