What is the speed of sound in air at 40°c?

355 m/s
307 m/s
331 m/s
239 m/s

For the car in the picture ,in which direction is the normal force? -into the screen -down -out of the screen -up

The energy produced as a result of this flow of electrons from atom to atom is called

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=