I'm having trouble with a few vector questions from the Essential's textbook
(bolded are the questions I can't do). Any help would be great

Exercise 2B
Q8. The vectors
and
are linearly dependent. Find the value of
.Q30. A light plane takes off (from a point which will be considered as the origin) so that its position after a short period of time is given by
1
where

is a unit vector in the east direction,

is a unit vector in the north direction and measurements are in kilometres.
a) Find the distance of the plane from the origin
b) The position of a second light aircraft at the same time is given by
2
Find:
i -
1
2ii - the distance between the two aircraft
c) Give a unit vector which would describe the direction in which the first aircraft must fly to pass over the origin at a height of 900m.Q32. A ship leaves a port and sails on a bearing of NE for 100 km to a point

.

and

are vectors in the east and north directions respectively.
a) Find the position vector of point

.
b)

is a point on the shore with position vector

Find:
i -
ii - the bearing of
from 
(Sorry didn't know how to write the arrow above the vectors)
Thanks!