Questions on Kayaking with other Boats present

Hello.  I hope these following questions dont appear to be rather silly,
but,  I feel i need to ask them out of concern for my safety when
Kayaking on a lake .  I just bought a new Sea Eagle 330 Inflatable Kayak
and am ready to take it out on some lakes . Theres one particular Island
that id like to paddle to which is perhaps a 1/4 mile from shore.  There
are motorboats on this lake although it never appears too busy.
Questions are :

1.  Will an 11'  Kayak that is approx. 30" wide , off white and blue in
color, be readily seen if a boat and kayak are heading head-on toward
one another.?

2.  What is a safe margin of distance i should expect a boater to take
to my kayak,  when out on the lake  ?  

3.   Are there many Boat/Kayak accidents on lakes generally ?

4.  What measures should i take if a Boat is coming fast toward me and
apparently doesnt see me ?  Stand up and wave a paddle ?    

Thanks, Dave