Your firm is considering investing in a new project. If the economy is strong (30% probability), you expect an NPV of $500,000; if the economy is normal (50% probability), you expect an NPV of $400,000; and if the economy is weak (20% probability), you expect an NPV of $300,000. What is the expected NPV of the project? 

a. $390,000 

b. $400,000 

c. $410,000 

d. None of the above