Evaluate the Sum Using the Given Information $x _ { 1 } = 2 , x _ { 2 } = - 2 , x _ { 3 } = - 4 , x _ { 4 } = - 3$

Multiple Choice

Evaluate the sum using the given information.
- $x _ { 1 } = 2 , x _ { 2 } = - 2 , x _ { 3 } = - 4 , x _ { 4 } = - 3$ , and $\Delta x = - 0.9 ; f ( x ) = \frac { 5 } { 2 x + 1 }$
4
$\sum _ { i = 1 } f \left( x _ { i } \right) \Delta x$ (Round to the nearest tenth, if necessary.)

A) $0.9$
B) $2.1$
C) $- 0.9$
D) $1.8$