Consider the following reaction: 3A -> 2B
When a mole of A is used up, what is the change in moles of B?
O-2/3
O +2/3
O 3/2
O +1

Sorry i dont understand the question can you rephase it?

Ithink iit might be

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.