Technician A says that a first-degree burn occurs when the skin is severely damaged and that it should have ice placed on it for relief. Technician B says that first-degree burns can be caused by ultraviolet light. Who is correct? a. Technician A only
b. Technician B only
c. Both Technicians A and B
d. Neither Technician A nor B

Apinion having 30 involute teeth of 6,5 module rotates at 220 r/min and transmits 2 kw to a gear wheel having 70 teeth; the addendum on both wheels is 4 of the circular pitch and the angle of obliquity is 200. determine; 3.1 the lengths of the path of approach and the arc of approach 3.2 the normal force between the teeth at an instant when there is only one pair of teeth in contact