Questions about circuits and Resistors

[taculator]

Homework Statement

http://www.sewanee.edu/physics/PHYSICS102/Ch28.pdf
On this link, can anybody explain to me how to set up problems 1-5?
The answers are on the page, but I have no idea how to group the resistors together to find their equivalent resistance...
Please I've been working on this for hours and i cannot figure it out

Homework Equations

V=IR
P=V^2/R

The Attempt at a Solution

 

[shungun]

resistors in series will be Rtotal = R1+R2+R3...
resistors in parallel will be 1/Rtotal = 1/R1 + 1/R2 + 1/R3...
Now look at question one for example, the resistor(2R) diagonally placed is in fact parallel to the 2 resistors with value of R bottom right and bottom, in turn these two resistors are in series.

and finally the net resistance of this series and parallel combination is in series with the resistor (R) which is at the top.
Now you can figure out what the net resistance is and you are done =) if you get confused try "redrawing" the circuit in a way you can visualize the series and parallel combinations.