Anchor: And you have to keep experimenting with alterations and examining the results as external conditions change over time.
Entailed: As external conditions change and time passes, you have to experiment with different alterations. 
Contradiction: Time will pass but the external conditions will stay the same, so you don't need to continue to examine the results. 
Contradiction: In the late 1960s they began a campaign to discourage the use of welfare and food stamps.
Contradiction: The district is a provider of water service to Alpaugh and now faces either a raise of its monthly fee or the option to go without undrinkable water.
Contradiction: The men are looking at each other.
Contradiction: The Postal Service regularly collects a representative sample of street delivery costs