Commutative number lines II

This task is about using number lines to show number sentences.
a)  Write the number sentence that each number line shows in the boxes below.
 
three number lines
b)
Use the number lines below to draw in each number sentence. 
 
i) 8 + 7 = 7 + 8
 

 
 
ii) 16 + 9 = 9 + 16
 

 
 
iii) 13 + 19 = 19 + 13