How do we gather most of the information we get about the universe around us?
a. by touching the things about which we are learning
b. by mechanical and electromagnetic waves bringing us the information to us
c. by telepathy (esp)

Four point charges each having charge q are located at the corners of a square having sides of length a. find symbolic expressions for the following. (a) the total electric potential at the center of the square due to the four charges (use any variable or symbol stated above along with the following as necessary: ke.) vtotal= (b) the work required to bring a fifth charge p from infinity to the center of the square (use any variable or symbol stated above along with the following as necessary: w=