A box of weight 20N rests on a horizontal floor. A maximum horizontal force of 6N is required to move the box along the floor .If the weight of 10N is added to the box , find the minimum horizontal force required to move the box.​

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.)