please help me answer this RED circle questions

THE RELATIONAL MODEL OF DATA !Exercise 4.7 Suppose relations R and S have n tuples a spectively. Give the minimum and maximum numbers of tuples that the results of the following expressions can have. nd m tuples, re- ac(R) x S, for some condition C. Mex mn um )TL (R)-S, for some list of attributes L. Men ; n Ne, ! Exercise 4.8 : The semporn of relations R and S, written R t S, is the set of tuples t in R such that there is at least one tuple in S that agrees with t in all attributes that R and S have in common. Give three different expressions of relational algebra that are equivalent to R S. ! Exercise 4.9 : The antisemijoin R