Would the following behaviors be considered selfish and/or unethical?

By selfish, I mean “devoted to or caring only for oneself”.

I treat “selfish” and “unethical” as separate adjectives for an action. An act can be selfish but ethical (not offering a terrorist a ride). An act can be unselfish but unethical (doing something out of love that violates laws or ends up hurting people). Other combos are possible.

All scenarios are hypothetical.
1. Each student is assigned a pair of safety goggles. Joe grabs his own pair of safety goggles but would not grab Mike’s pair for Mike even though Mike’s pair is right next to Joe’s.

2. People are rushing onto the bus with no line. All of them are equally capable individuals. There is only one space left on a bus. Kevin happens to enter the bus before anyone else and thereby, claimed the remaining space.

3. Tina is sitting on a bus. There is an empty seat next to her. A young lady is standing in the aisle. Tina offers the young lady the seat next to Tina. The young lady shakes her head and says it’s all good. Tina puts her heavy backpack on the empty seat. (I assume there is no law that says that one can only occupy the seat one paid for).

4. Minisoft Corp. sets up a table and gives away free pens. Assume Minisoft has a huge supply of pens. Bob grabs a pen even though he likes Orange Computer, a direct rival to Minisoft, and would never dream of using Minisoft’s products.

5. Allan is a very smart but shy boy. One of his classmates, Joyce, who is known to be a slacker, wants Allan to explain a math problem to her. Allan is under no duty to Joyce (i.e. they are not math partners, etc.) and they in fact do not know each other very well. Allan shakes his head and says he is busy.