Kate is researching air pollution and finds some information on ozone. she knows that ozone is a good thing as part of the ozone layer, so why is it also an air pollutant?
a) at ground level, ozone contributes to smog.
b) we breathe out ozone, adding it to the atmosphere.
c) ozone breaks into carbon dioxide.
d) it contributes to global warming.

Haley rubs a cotton cloth along a plastic strip. the plastic strip becomes positively charged. why did this happen? a. the plastic strip gained protons from the cotton. b. the plastic strip lost protons to the cotton. c. the plastic strip gained electrons from the cotton. d. the plastic strip lost electrons to the cotton.

One day, after pulling down your window shade, you notice that sunlight is passing through a pinhole in the shade and making a small patch of light on the far wall. you see that the patch of light seems to be a circular diffraction pattern. it appears that the central maximum is about 1 cm across and you estimate that the distance from the window shade to the wall is about 3 m. what is (a) the average wavelength of sunlight? (b) the diameter of the pinhole?

Select all of the following that are equal to an impulse of 20 unitsa) force= 5, time= 5.5b) force= 25, time= 0.8c) force= 0.1, time= 200d) force= 10, time= 2(its b, c, and d)(also in order to find answer they have to add to get the unit)ex= 25x.8=20 or .1x200=20