• A ton can be considered as a unit of volume.
• Some scientists look ( up ) on matter as being concentrated energy.
• The photons can be thought of as a wave with ...
• The shock front constitutes a sufficiently sharp transition to be regarded ( or viewed ) as a mathematical discontinuity.
• We take it as convincing evidence that single heavy atoms are ...
• The ions in certain salts may not be treated as hard spheres.
• These trajectories are seen as the shortest paths that ...
• The theory treats these forces as different manifestations of ...