I need help with a spring constant question, can someone solve this?

What is the radius of the circular path ofa charged particle in a magnetic field?

The pressure, volume, and temperature of a mole of an ideal gas are related by the equation pv = 8.31t, where p is measured in kilopascals, v in liters, and t in kelvins. use differentials to find the approximate change in the pressure if the volume increases from 14 l to 14.6 l and the temperature decreases from 375 k to 370 k. (round the answer to two decimal places.)

When the force acting on an object points at least partially in the direction of the motion the work done is considered to be negative