Is cutting a string physcal or chemical change

When objects are charged by they do not need to touch each other. a. friction b. induction c. conduction d. all of these

The temperature at a point (x, y) is t(x, y), measured in degrees celsius. a bug crawls so that its position after t seconds is given by x = 6 + t , y = 8 + 1 3 t, where x and y are measured in centimeters. the temperature function satisfies tx(3, 9) = 5 and ty(3, 9) = 4. how fast is the temperature rising on the bug's path after 3 seconds? (round your answer to two decimal places.)

Positrons are spontaneously emitted from the nuclei of