Assertion: mercury's period | /r/HasProperty | required for expected return
Facets:
value: on those investments
type: OTHER
Source sentences:
text: The main impediments to commercial exploitation of these resources are the very high cost of initial investment, the very long period required for the expected return on those investments (The Eros Project plans a 50-year development), and the fact that the venture has never been carried out before—the high-risk nature of the investment.