4. Place the following steps of glycosylation in order:

a. The carbohydrate is further modified by addition, subtraction or post-transnational modification (such as phosphorylation)

b. Dolichol-phosphate is inserted into the membrane

c. The core glycosylation is transferred to an asparagine residue on the protein

d. A core carbohydrate made up of 2 N-acetyl glucosamine, 4 mannose and 3 glucose molecules is built

Where in the cell do each of these steps (a-d) occur?