Observation: You saw/ observed something and you are stating that.
Inference: You are predicting something to be true. If so and so, then this will occur.
<span>a = 25-13/6 = 12/6 = 2 m/s^2
Av speed: 25+13/2 = 38/2 = 19 m/sec
Dist = speed * time
19 * 6 = 114 meters</span>
It looks blue as it is only reflecting blue light
-- Volume . . . made out of 3 dimensions of length
-- Density . . . made out of mass, and 3 dimensions of length
-- Area . . . made out of 2 dimensions of length
-- Acceleration . . . made out of length and time
<em>Mass</em> is not made out of anything else. It's fundamental. A few other fundamental things are length, time, and electric charge.