Construct a formal proof of validity for each of the following arguments, using the suggested notation in each case If prices fall or wages rise, then both retail sales and advertising activities...

Construct a formal proof of validity for each of the following arguments, using the suggested notation in each case

If prices fall or wages rise, then both retail sales and advertising activities increase. If retail sales increase, then jobbers make more money. Jobbers do not make more money. Therefore, prices do not fall. (P, W, R, A, J)