3. What surface feature could be associated with this underground feature?
A. alluvial fans
B. tower karst
C. sinkholes

The answer to your question would be c. mineral oil  

Answer heart of american                  live in harmony                    hillsides of orchards                    blaze of color                    backdrop of pines;

The population of unionid mussels decreased after zebra mussels were introduced. zebra mussels competed with the unionid mussels for food. the zebra mussels were able to displace the unionid mussels, allowing the zebra mussel population to increase  over the years. the unionid mussel population decreased because  of lack of food.

Self-ionizes to form an equilibruium system in which [ h_{3} o^{+} ]=[ oh^{-} ]=10^{-7} m