Have you ever been scared?

Ineed the answer to question 1 , i’m desperate

Astudent creates a model of a closed ecosystem by filling a glass tank half full with water, then adding 10 snails and two small aquatic plants. the next day, all the snails are dead. what is the most likely cause of their death?

Explain the comparisons between nature and packingtown that appears on pages 81 and 82 answer