I need help with the following Discrete problem. Please show your work, thank you!

2. Let K(x,y) be the propositional function "x knows y." The domain of discourse is the Cartesian product of the set of students taking discrete math with itself (i.e., both x and y take on values in the set of students taking discrete math). Represent the assertion "someone does not know anyone" symbolically. Write the negation of this assertion symbolically and in words