Why are atoms electrically neutral?

What is work? how much work is done to move an object 0 meters?

Which changes of state do the labels represent? a: b: c:

Juan created a chart to him study for a test. which headings best complete the chart? x: transparent objects y: opaque objects x: opaque objects y: transparent objects x: high frequency waves y: low frequency waves x: low frequency waves y: high frequency waves