Bonnie is dusting the house and raises a cloud of dust particles as she wipes across a table. if two 3.5 x 10-14c pieces of dust exert an electrostatic force of 4.1 x 10-12n on each other, how far apart are the dust particles at that time?

When a vertical beam of light passes through a transparent medium, the rate at which its intensity i decreases is proportional to i(t), where t represents the thickness of the medium (in feet). in clear seawater, the intensity 3 feet below the surface is 25% of the initial intensity i0 of the incident beam. what is the intensity of the beam "10" feet below the surface? (give your answer in terms of i0. round any constants or coefficients to five decimal places.)