Write an Equation for the Function That Is Described by the Given

Multiple Choice

Write an equation for the function that is described by the given characteristics. ​
A cosine curve with a period of 4π,an amplitude of 7,a right phase shift of $\frac { \pi } { 2 }$ ,and a vertical translation up 2 units.
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A) $y = 2 + 7 \cos \left( \frac { x } { 2 } - \frac { \pi } { 4 } \right)$
B) $y = 2 + 7 \cos \left( \frac { x } { 2 } + \pi \right)$
C) $y = 2 - 7 \cos \left( \frac { x } { 2 } - \frac { \pi } { 4 } \right)$
D) $y = 2 + 7 \cos \left( \frac { x } { 2 } - \pi \right)$
E) $y = 2 + 7 \cos ( x - \pi )$