Answer:
180 ways
Step-by-step explanation:
Aerospace companies (A) = 5
Energy development companies (D) = 3
Electronics companies (E) = 4
Number of aerospace stocks bought (a) = 2
Number of Energy development stocks bought (d) = 2
Number of Electronics stocks bought (e) = 2
The number of ways that the investor can select his six investments from the recommended list is given by the combination of picking two out five aerospace companies, multiplied by picking two out three energy development companies, multiplied by picking two out four electronics companies:
There are 180 ways for the investor to select the six companies.