Question 1
In a product topology, what does a basic open set usually look like?
Question 2
For the product topology on $X \times Y$, which family is a basis?
Question 3
Which statement best describes the projection map $\pi_1 : X \times Y \to X$ in the product topology?
Question 4
Suppose $X \times Y$ has the product topology and $U \subseteq X$, $V \subseteq Y$ are open. What can be said about $U \times V$?
Question 5
Which set is a typical basis element in the product topology on $\mathbb{R}^2$?