There's a way to make an approximate guess if it's a boy or girl with the head spot, until you get used to it it's really difficult. I'd suggest go based on leg color if you want to guess at genders the girls will most often have a black wash over their legs and the boys usually won't. There are...
That's a barred rock. The rose comb gene has a partial dominance so if he had even one gene with the rose comb you'd be able to tell. This guys comb isn't entirely straight, but it is only a single comb. :)