Nick starts with 20 mg of a you active substance dumb mouth of the substant decreases by 1/2 each week for a number of weeks w he writes the and pressure expression to wani parantheses of 1/2 parentheses w to find their mouth of radioactive services remaining after w weeks

Amass weighing 16 pounds stretches a spring 8/3 feet. the mass is initially released from rest from a point 2 feet below the equilibrium position, and the subsequent motion takes place in a medium that offers a damping force that is numerically equal to 1/2 the instantaneous velocity. find the equation of motion if the mass is driven by an external force equal to f(t)=cos(2t).