#1 looks like Struck Through Grease
on the left wheat and maybe a struck through on the "E" of UNITED but not sure with the pic provided, may just be damage.
#2 I agree with JimmyD, a plating bubble.
#3 Looks like a die chip, sometimes referred to as a "bug". Maybe take a look at LIBERTY, sometimes there will be a corresponding die chip and maybe a BIE.