Read the following information to answer the given questions.
Six lectures $A, B, C, D, E, F$ are to be organised only on one each day from Monday to Sunday in accordance with the following..
- $C$ should not be organised on Friday.
- $A$ should be organised immediately after $D$.
- There should be a gap of two days between $B$ and $F$.
- On one day there will be no lecture (Saturday is not that day), just before that day $F$ will be organised.
- $E$ should be organised on Wednesday and should not be followed by $F$.
How many lectures are organised between $F$ and $D$ ?