9. The following question has two parts. Answer Part A first, and then Part B. Part A From the details in the selection from Silent Spring, what can
you conclude about the town before the changes take place?
a. The town attracts visitors who enjoy outdoor activities.
b. The town is full of simple, poor, hard-working people.
C. The town is a settlement for recent immigrants.
d. The town is located in an industrial area.

Keeping in mind the life cycle of bacteriophages, consider the following problem: during the reproductive cycle of a temperate bacteriophage, the viral dna inserts into the bacterial chromosome where the resultant prophage behaves much like a trojan horse. it can remain quiescent, or it can become lytic and initiate a burst of progeny viruses. several operons maintain the prophage state by interacting with a repressor that keeps the lytic cycle in check. insults (ultraviolet light, for example) to the bacterial cell lead to a partial breakdown of the repressor, which in turn causes the production of enzymes involved in the lytic cycle. as stated in this simple form, would you consider this system of regulation to be operating under positive or negative control?

The steps in the formation of extrusive igneous rocks are listed below in an incorrect order: 1. rock melts due to high temperature. 2. rock is buried deep under earth's surface. 3. magma is forced out of earth's surface during volcanic eruption. 4. lava cools and crystallizes to igneous rock. which of these best shows the correct order of steps in the formation of extrusive igneous rocks? 1, 3, 4, 2 2, 1, 3, 4 3, 4, 2, 1 4, 2, 1, 3

9. the history of life on earth is recorded in