1. You have an isotope with a half-life of 200 years. How much of the original material is
left after 600 years? (Answer with a fraction or percent)

What would happen to the nutrients in an ecosystem if decomposers, such as bacteria, didn’t exist there?

Which of the following is a consequence of urban heat islands? increased precipitation downwind of the city? increased precipitation upwind of the city? decreased winds within the city? increased winds within the city?

Imagine that certain laws of physics could be ignored and you were able to travel vast distances in moments. now imagine that you traveled to an earth-like planet located light-years away that is known to support life. think about what you’ve learned in this unit and make an argument for what you think would be the dominant type of life form on this planet. consider whether a notochord is required for an organism to manipulate its environment and become a dominant creature.