Which scientist discovered DNA after experimenting with white blood cells

If the force on an object is in the negative direction, the work it does on the object must be [2 points a) negative. b) positive c) the work could be either positive or negative, depending on the direction the object moves

The current in a hair dryer measures 11 amps. the resistance of the hair dryer is 12 ohms. what is the voltage?unit:

What is the energy of a photon of ultraviolet radiation with a frequency of 4.4 × 1015 hz? planck’s constant is 6.63 × 10–34