1. From which period is a rock at +2.7 m depth? A. Paleogene
B. Cretaceous

2. What is the average iridium content of rock 0.5 m below the K–Pg boundary layer?

A. 0.25 ppb
B. 0.30 ppb
C. 0.36 ppb
D. 41.6 ppb

3. How much more iridium was found in the K–Pg boundary layer than in rock 0.5 m below it?

A. 41.35 ppb
B. 41.60 ppb
C. 41.24 ppb
D. 39.62 ppb

The collared lizard is a species found in the desert southwest. male collared lizards show considerable color variation, ranging from brightly colored to a very dull pattern. your goal is to determine the function, if any, of male color patterns in collared lizards, using the scientific method. your tentative explanation is that male color plays a role in attracting females for mating purposes. you predict that females will preferentially choose brightly colored males over dull-colored ones. to test this prediction, you observed the interactions of female collared lizards with their male counterparts. you selected males that were the same age and size, and that differed only in their coloration pattern. you placed equal numbers of the two types of male lizards, bright and dull, in aquariums, along with one female lizard per aquarium. out of 350 aquariums observed, the female chose to mate with the brightly colored male 277 times, and the dull-colored male 70 times. in 3 instances, the females did not mate with either type. create a bar graph of your data, plotting the type of male (dull or brightly colored) on the x-axis. on the y-axis, plot the frequency with which each type of male was chosen by females. using this graph, answer the following question(s). is it reasonable to conclude (i.e., is it supported by the data) that female collared lizards prefer more brightly colored male lizards over dull-colored males?

Models are non-visual ways of coummincating how someone thinks about something in the natural world

When elements that form a mineral dissolve in hot water, they form a mixture called a(n) a)geode b)vein c)evaporation d)crystallization e)magma f)lava g)solution h)gem