An elliptical staircase that decreases can be modeled by the parametric equations x = rcos(t) y = rsin(t) z = ht/n where r = ab/[bcos(t)2

An elliptical staircase that decreases can be modeled by the parametric equations
x = rcos(t) y = rsin(t) z = ht/Ï€n
where r = ab/ˆš[bcos(t)2 + [asin(t)2, a and b are the semimajor and semiminor axes of the ellipse, h is the staircase height, and n is the number of revolutions that the staircase makes. Make a 3-D plot of the staircase with a = 20m, b = 10m, h = 18m, and n = 3. (Create a vector t for the domain 0 to 2Ï€n, and use the plot 3 command.)

20 20 10 in -10-20