The weight of oranges growing in an orchard is normally distributed with a mean weight of 8 oz. and a standard deviation of 2 oz. What is the probability that a randomly selected orange from the orchard weighs less than 4 oz., to the nearest thousandth?

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).