Solve for the Specified Variable $I=\frac{E}{R+r}$ For $r$ A) $r=\frac{I R}{E}$ B) $r=\frac{E}{I}-I R$

Multiple Choice

Solve for the specified variable.
- $I=\frac{E}{R+r}$ for $r$

A) $r=\frac{I R}{E}$
B) $r=\frac{E}{I}-I R$
C) $r=\frac{E-R}{I}$
D) $r=\frac{E-I R}{I}$