A body starting from rest moves with uniform acceleration until it attains a speed of 100m/s after 20 s. It maintained this speed for the next 30s and came to rest by  uniformly deceleration in 30s. (a.) Find its acceleration.

Laboratory experiments, observational field studies, and model-building are all examples of different forms of scientific investigations.  in what way do laboratory experiments primarily differ from other forms of scientific investigations?   a.  a laboratory experiment is the only accepted form of investigation within the scientific community.  b.  studies about how things behave in nature or studies involving very large objects are best answered through laboratory experiments.  c.  laboratory experiments involve the identification and control of variables.  d.  data can only be generated through laboratory experiments, not other forms of investigation.

How many molecules are present in 3 mols of silicon dioxide (sio2)?

Which is the best for showing percentages of different types of cars sold(gas hybrid , electric , other ) in the united states ?