Which expressions are equivalent to (4 • a) • 2

Choose all that are correct

A: 4 • (a • 2)

B: 2 • (4 • a)

C: 4 • 2 • a • 2

D: 8a

E: 4 • 2 + a • 2





2nd Question:
Which statement shows the associated property of addition?

A: 21 + 2y = 2y + 21

B: If m + 3 = 18, then 18 = m + 3

C: 3 • (5 • x) = (3 • 5) • x

D: (u + 7) + 13 = u + (7 + 13)

I think its A but I'm not sure.





3rd question:
What is another way to write the expression p • (10 - 2) ?

A: (10 • 2) - p

B: 10 • 2 - p

C: (10 • 2) • p

D: (p • 10) - (p • 2)




please help I suck at this.