Microeconomics;A jewelry firm rents factory space, uses equipment and hires workers to produce necklaces

$ per necklace7065T-10,00060ATCT-20,00055T-30,0005045MC105510152025303540quantity of necklaces per hourA jewelry firm rents factory space, uses equipment and hires workers to produce necklaces using a constant returns to scale production technology. The figureshows short-run average total cost (U-shaped curves) and marginal costs (increasing curves) for three different factory sizes, T=10,000, T=20,000 andT=30,000. If the firm wanted to produce 30 necklaces per hour, what size factory should it choose in the long-run?the firm could select any size