7a) If you draw a diagram with i on the x axis and j on the y axis then you can use the tan to find the argument.

In your case it is

. Since this is taken from the horizontal the vertical (bearing) will be 90 minus your answer:

The speed component is given already

8a) If two vectors are parallel thenb= kawhere b and a are vectors and k is a constant:

Equate the j component:

Equate the i component: to get a = 0.5