1a) Which equation demonstrates the commutative property of addition for complex numbers? A: (5 - 10i)[(0 - 10i) +(5 +0i)] = [(5 - 10i)(0 - 10i)]+[(5 - 10i)(5 +0i)]

B: (10 - 5i) + (5 - 10i) = (5 - 10i) +(10 – 5i)

C: (5+ 10i)+(- 5 - 10i) = 0+ Oi

D: [(0 - 5i)+(5-i)] +(5 +i) = (0 - 5i)+[(5 - i) +(5+i)]

1b) Which of the following demonstrates the commutative property of multiplication?

A: (8+6i)(4+2i)=(4+2i)(8+6i)

B: (7-6i)(0+2i)=(7+2i)(0-6i)

C: (2+8i)(2-8i)=20

D: (-5+3i)(-1+i)=(5-3i)(1+i)