Athin disk with a circular hole at its center, called an annulus, has inner radius r1 and outer radius r2. the disk has a uniform positive surface charge density σ on its surface.

Which statement best describes resistance? resistance is a. how well a current will flow in a material and is measured in volts. b. how well a material conducts an electrical charge and is measured in ohms. c. the ability of a material to attract a positive charge to create a current. d. the ability of a material to repel neutral charges and is measured in ohms.

Apatient has a history of poor nutrition. he has skin rashes, bleeding gums, and a cut that hasn’t healed in a long time. what vitamin deficiency most likely caused this symptom?

Which levels of government establish and implement educational requirements for minors