I don't understand why the answer for a, b, c, and d is like that, can you help me?

2. [2 points per part] Suppose u and v are 3D vectors that look like this: That is, u points along the positive x-axis, and v is in the yz-plane. (You don't have to show work on this problem.) y Identify the following values as positive, negative, or zero. (Circle your answer.) (a) u . V: positive negative zero (b) The x-component of u X V: positive negative zero (c) The y-component of u X v: positive negative zero (d) The z-component of u x v: positive negative zero