$7\mathrm{.}23$ Why do analysts draw multiple sets of DFDs$?$

$7\mathrm{.}24$ How can DFDs be used as analysis tools?

$7\mathrm{.}25$ Explain the guidelines for deciding when to stop decomposing DFDs$.$

$7\mathrm{.}26$ How do you decide if a system component should be represented as a source$/$sink or as a process?