Answer:
B and E
Step-by-step explanation:
it is given in the question that
Alpha printing will make 400 brochures for $100. Omega printing will make 1,000 brochures for $100.
For Alpha, cost of 1 brochure is

For Omega,
Cost of 1 brochure is

So choosing Omega printing, you will save

on each brochure .
60% if there are only 10 white and black balls