What causes a sound wave to echo in an empty house? A. Transmission of waves from a person speaking
B. Reflection of waves off smooth walls
C. Refraction of waves by a person speaking
D. Absorption of waves by rough walls

16 select the correct answer from each drop-down menu. sharks, whales, and dolphins share similar features such as body shape and the position of fins. hoy while whales and dolphins have lungs. these differences indicate that the organisms share a comme whales also possess a vestigial pelvic bone. the presence of the pelvis bone may indicate that whales reset next