In the given diagram if AB || CD || EF, then which of the given options is true?
1
\(\rm\frac{1}{a}-\frac{1}{c}=\frac{1}{b}\)
2
\(\rm\frac{1}{a}+\frac{1}{b}=\frac{1}{c}\)
3
\(\rm\frac{1}{b}-\frac{1}{a}=\frac{1}{c}\)
4
\(\rm\frac{1}{c}-\frac{1}{b}=\frac{1}{a}\)