Put the following in correct order for endochondral ossification.

a. Mesenchymal cells of the embryo develop into cartilage-producing cells
b. The periosteum (formerly perichondrium) begins to produce a thin layer of compact bone
c. A hyaline cartilage model of the future bone is formed.
d. Cartilage is the midregion of the model becomes calcified.
e. Spongy bone tissue develops at the primary ossification center.
f. Secondary ossification centers produce spongy bone tissue of the epiphyses.
g. Medullary cavity is formed.