The popular notion that a tree's age can be determined by counting the number of internal rings in its trunk is generally true. however, to regulate the internal temperature of the tree, the outermost layers of wood of the brazilian ash often peel away when the temperature exceeds 95 degrees fahrenheit, leaving the tree with fewer rings than it would otherwise have. so if the temperature in the brazilian ash's environment never exceeded 95 degrees fahrenheit, its rings would be a reliable measure of the tree's age.
which of the following is an assumption on which the argument above depends?
(a) the growth of new rings in a tree is not a function of levels of precipitation.
(b) only the brazilian ash loses rings because of excessive heat.
(c) only one day of temperatures above 95 degrees fahrenheit is needed to cause the brazilian ash to lose a ring.
(d) the internal rings of all trees are of uniform thickness.
(e) the number of rings that will be lost when the temperature exceeds 95 degrees fahrenheit is not predictable

Astudent from one of the research labs is having trouble preparing a slide for examination and photographing. the bacterial slide that he has brought to you was prepared using a commercially purchased stain. he has asked for your in determining what he is doing wrong so that he can change the lab protocols and continue on with his project. after examining the slide under oil immersion, you determine that no bacteria are present even though the student is able to show you the culture he used to make that slide that has visible growth in the liquid medium. which of the following statements does not explain the fact that there are no bacteria present on the student’s slide? by not allowing a glass slide to completely air dry before heat fixation, the flame will cause the surrounding water to boil and this will damage the bacterial cell. overheating during the fixation step boiled the water within the bacterial cells and resulted in the cells bursting. insufficient heating of the slide did not drive out the thin layer of water and this resulted in minimal bonding between the bacteria and the glass slide. rinsing with alcohol during the washing step stripped the bacteria off the glass slide. rinsing with alcohol during the washing step stripped the bacteria off the glass slide.