Problem 4 (total 13 points) Please fill in the blanks for the definitions specified below. (a) are and some of the (non) commercial Database Management Systems. - 3 points. (b) Relational Data Model is based on the theory in Math. -2 points. (c) Consider two relations called R, and R2. The number of tuples in R, and R, are t, and tz respectively. The number of attributes of R, and Rz, on the other hand, are n and nz. (tu, tz, ni, n, >= 1). Fill in the blanks with formulae containing ty, tz, ni, na, functions, and constants. Each correct answer - 2 points. If we apply RESTRICT operator to the relation R, the result will contain a minimum of and a maximum of tuples. The result relation will have a minimum of and a maximum of attributes. If we apply PROJECT operator to the relation R2, the result will contain a minimum of and a maximum of tuples. The result relation will have a minimum of maximum of attributes. and a Assuming that Rand R, are union-compatible, If we UNION Rand Rz relations, the result will contain a minimum of and a maximum of tuples. The result relation will have a minimum of and a maximum of attributes. if we @JOIN R, and R2 over an attribute or a set of attributes), the result will contain a minimum of and a maximum of tuples. The result relation will have a minimum of and a maximum of attributes