Working with negative numbers

This task is about calculations with negative numbers.
illustration: artistic collection of numbers and symbols
 
Write down the answers to each of these equations.
 
a)   i)  
⁻6 × 3 = __________
 
You may want to use this space for working:

 

   ii)  
⁻4 × ⁻6 = __________
 
b)   i)  
⁻2 + 8 = __________
 
   ii)  
4 + ⁻9 = __________
 
c) i)
5 − 7 = __________
 
   ii)  
⁻2 − 5 = __________
 
   iii)    ⁻5 − ⁻9 = __________