In which situation is the speed of the car constant while its velocity is changing? The car travels down a straight track at 30 m/sec.
The car travels around a circular track at 30 m/s.
The car begins from rest and accelerates to 20 m/s.
The car begins traveling at 30 m/s and decreases to 15 m/s.

we can conclude that the melting point of table salt is above room temperature (it's actually 801 deg c). the melting point of mercury must be below room temperature (- 39 deg c).

c. electrical charges of ionic bonds.

qualitative observation deals with data that can be observed with our senses: sight, smell, touch, taste, and hearing. they do not involve measurements or numbers. for instance, colors, shapes, and textures of objects are all qualitative observations.