A scientific theory is. A. A well-tested explanation for a broad set of observations
B. A well-tested explanation for a widely accepted hypothesis
C. A proven explanation for the results of multiple experiments
D. A hypothesis that has stood the test of time

Which explanation describes the forces involved for a person to walk down the sidewalk? a. the person's feet push backward on the sidewalk; the sidewalk pushes backward on the person. b. the person's feet push forward on the sidewalk; the sidewalk does not push on the person. c. the person's feet push backward on the sidewalk; the sidewalk pushes forward on the person. d. the person's feet push forward on the sidewalk; the sidewalk pushes forward on the person.

Apatient has a history of poor nutrition. he has skin rashes, bleeding gums, and a cut that hasn’t healed in a long time. what vitamin deficiency most likely caused this symptom?

What component of earth’s atmosphere exists entirely as a result of photosynthesis?