Q: Which features are physical properties of an iron nail?
A: conducts heat, magnetic, solid
Q: Which discovery revealed that the universe contains many structures composed of millions of stars?
A: galaxies
Q: Which human activity has most negatively affected air quality?
A: burning coal
Q: A gastroenterologist is a doctor who treats problems of the esophagus, stomach, and intestines. Which organ system is cared for by this type of doctor?
A:
digestive system