In 1932, Giuseppe Momo was commissioned to build the famous Vatican Museum double spiral staircase. Suppose that it takes you one hour to stroll at a constant speed up one spiral of this staircase, which has a radius of 18 feet and a height of 50 feet and makes 5 revolutions. Assuming the spiral staircase is centered about the z-axis, find a vector parametric equation for the helical path you take from the point (28,0,0) to the point (28,0,40) that makes 4 revolutions during the time interval 0≤t≤1