Optimistic people: A. see the glass as half full.
B. attribute their successes to their own abilities.
C. have a higher chance of becoming depressed.
D. attribute their success to outside influences.

Can you use radiation to generate electricity

What is the difference between electrically neutral objects and electrically charged objects

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?