Jamil always throws loose change into a pencil holder on his desk and
takes it out every two weeks. This time it is all nickels and dimes. There
are 2 times as many dimes as nickels, and the value of the dimes is
$1.35 more than the value of the nickels. How many nickels and dimes
does Jamil have?

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.)