How do i figure out these problems ?

Given two vectors

they are parallel if they are a multiple of each other:

You can easily test this by checking if

they are orthogonal if their dot product is null:

For example, in the first case, we have

So, they aren't parallel. Similarly, you have

So, they aren't orthogonal.

In the second case, we have

So, they aren't parallel, and

So, they are orthogonal.

Finally, we have

So, they are parallel (and thus can't be orthogonal)

4

step-by-step explanation:

6 (donuts) divided by 3 is 2.

so 2/3 means 2 times 2, which is 4/6.

you get two and your friend gets four.