Game Theory Question
Here are a couple hints for the two that you haven't answered:

The prisoner's dilemma is characterized by the inability to sustain the Pareto optimal payoff as a Nash Equilibrium due to the existence of a profitable deviation for both players. Each player has a dominant strategy to "Defect" and so the unique Nash Equilibrium is one where both players "Defect". Does that hold here?

A (possibly mixed) strategy $a$ (weakly) dominates another strategy $b$ for a given player $i$ if player $i$ (weakly) prefers playing $a$ to $b$ for any strategy vector of the other players. In your case, there is just one other player, $j$, and so $i$ simply has to prefer $a$ to $b$ for any strategy played by player $j$. 

You just need to see if that holds for your two players.