Robin is designing a target with centre .

The diameter of the smallest circle is 36 cm.
 

 
Robin makes    and  .

What is the diameter of the whole target, ?

A traffic light is 2.4 m tall. Its shadow from a nearby floodlight is 3 m long.
 

 
What is the height of the floodlight?

Trapeziums and are similar.
 

What is the distance from to ?