Figure 3-13 shows the development of entity clusters for the Pine Valley Furniture E-R d...

Figure 3-13 shows the development of entity clusters for the Pine Valley Furniture E-R diagram. In Figure 3-13b, explain the following:

Reference figure 3-13

a. Why is the minimum cardinality next to the DOES BUSINESS IN associative entity coming from CUSTOMER zero?

b. What would be the attributes of ITEM (refer to Figure 2-22)?

c. What would be the attributes of MATERIAL (refer to Figure 2-22)?

Reference figure 2-22