varies state to state,
illinois - clear front reflector, red rear reflector visible from 100 ft, pedal reflectors, wheel reflectors, bell/horn that can be heard from 100 ft
at night - front - light visible from 500 ft, rear red light visible up to 600 ft
helmets not required (no helmets for motorcycles required either)
really tho ive never seen anyone get in trouble for no reflectors/horn/lights, only seen people get in trouble for riding on sidewalks or "loitering" in parking lots.
i like having lights on my bike tho i do ride without em sometimes if not going far, i dont mind reflectors either but i prefer round reflectors, and i think wheel reflectors are ugly but leave em on anyway.