“Door”

The dark-haired woman was named Volosh. An expert in the study of footprints, she was among the second batch of beta testers.

"Did they have any disguises on their faces?" Pushna inquired.

"Yes, very cautious," said Volosh,  "One looked around 185cm tall, lean build, black athletic wear. The other maybe 175cm, average build, dark blue hooded sweatshirt..."

"If masked, how'd you judge ages?" Pushna interrupted.

"Gait and movement. Intuition from experience," Volosh said briefly. "Didn't you take footprint analysis electives in college?"

"My major was investigative studies. I have only a superficial knowledge of footprint analysis, so I'm essentially a layman in that regard," Pushna replied, feeling she was like a student being quizzed by a professor.

Volosh chuckled, "It shows. You're rather unpolished. You need more practice."