If the radius of the cone is 3ft. and the volume is approximately 38ft*3, find the approximate height Show Work or Explain Work

Based on what i know about mean, this doesn't add up.

Adepartment store purchases screen-printed t-shirts at a cost of $5 per shirt. they mark up the price 150% (making the selling price 250% of the store's purchase price) and put them on the sales floor. every month that a t-shirt doesn't sell, the store reduces the selling price by 25%.

What is the solution to the equation in the & show work i’m very