For Conditionally formatting the cells, first select the range to affect.. then go to Home|Conditional foratting and select New Rule. Then select (use a formula to determine which cells to format) from the top section and enter
Click Format and choose for the appropriate tabs to get desired effects.
To hide the rows, you will need VBA and an event macro.
To do this, right-click the tab of the current sheet (at the bottom) and select View Code, then paste the following into the editor Window:
and close the window.
Private Sub Worksheet_Change(ByVal Target As Range)
If Target.Address = "$C$4" Then
On Error Resume Next
Application.EnableEvents = False
If UCase(Target.Value) = "N" Then
Range("5:15").Rows.EntireRow.Hidden = True
Range("5:15").Rows.EntireRow.Hidden = False
Application.EnableEvents = True
On Error GoTo 0
Then test by changing the values in C4