Which pair does NOT have an electric force between them? a positive object and negative object two positive objects two neutral objects two negative objects

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.

If a spring has a k value of 100 newtons per meter and it is stretched 0.50 meters, what is the restoring force of the spring?

Acar travels 40m in 8 seconds find the car speed