Integrated Science- 8th grade science Please Help ASAP!
Its almost the end of semester And I need to fix my grade for science so PLEASE help!
its almost report cards time!

Which statement best explains why an object weight less on mercury than it does on earth

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.)

The image shows a pendulum in simple harmonic motion the pendulum starts at a and swing to e