At 7 weeks old, with an RIR parent, I guess female. Even with a pea comb, it is pale for a 7 week old male.
I can't see so well, they seem to be neither particularly thick (rooster) nor obviously slender (hen). But they seem more female-like than male-like.
Definitely female stance, it could get more upright later, indicating rooster. But in both photos its stance is very female.
There are other factors, such as color, but I am uncomfortable advising based on those due to inexperience. My reaction is female, but hopefully others will respond as well. It can be hard to tell with crosses sometimes.