Alist of environmental issues is shown below.
• rabbits transported from europe overrun and
deplete farmlands in australia.
• many areas in the southeastern united states
are overgrown with the kudzu plant from asia.
• in parts of new york state, bluebirds must
compete with starlings originally brought here
from england.
all of these issues are the result of
(1) introduction of nonnative species into stable
ecosystems
(2) genetic engineering without using adequate
safety precautions
(3) preservation of habitats due to human
population growth
(4) use of foreign species to replace native
predators

The table shows dates and appearance of index fossils. which rock layers can be dated most precisely? a) a layer containing both a fossil 4 and a fossil 3 b) a layer containing both a fossil 2 and a fossil 3 c) a layer containing both a fossil 1 and a fossil 4 d) a layer containing both a fossil 1 and a fossil 2

The human genome project is devoted to mapping the general dna sequence of our species. this could lead to the development of new medicines, as well as the possibility of using gene therapy to treat certain diseases. however, there are some ethical issues surrounding the mapping of individual genomes. one concern is a) that your genes may change over time, making the project useless. b) that insurance companies could discriminate based on genetic make-up. c) that since this has never been done before, we should probably not do it now. d) that sequencing our individual genomes is so expensive, it is a counter-productive strategy.

What noticeable trend from this graph might be used to make a conclusion?