A plane is traveling 20 m/s East. The wind is blowing 10 m/s North. What is the net velocity of the plane

Which of the following represents an upright image? a. -do b. +m c. -m d. +do

Light from a sodium lamp passes through a diffraction grating that has 1000 slits per millimeter. the interference pattern is viewed on a screen 1.000 m behind the grating. the first (m = 1) two bright yellow fringes that are visible are 0.7288 m and 0.7300 m from the central maximum. what are the wavelengths of these two fringes?

If the chemical properties of a substance remain unchanged and appearance or shape of a substance changes it is called a ?