Which is a trait of an index fossil? a. resembles a living species b. found in a limited area c. found in a limited time span d. a particular kind of organism

Type the correct answer in each box. use numerals instead of words. if necessary, use / for the fraction bar. the following chemical equation shows the combustion of ethane. balance the equation by filling in the coefficients. c2h6 + o2 → co2 + h2o

Match the following terms describing electrical events with the correct phases of the cardiac cycle. the ventricular muscle cells depolarize at the start of this phase. during this phase, na+ entry through the funny channels causes the pacemaker potential of sa nodal cells to gradually become less negative until it reaches threshold. the ventricular muscle cells repolarize right before this phase. the cytosolic concentration of calcium in the contractile cells of the ventricle is highest during this phase. a. isovolumetric relaxation b. ventricular ejection c. isovolumetric contraction d. ventricular filling

Which excerpt from the land, part 4 best supports the claim that paul is a talented horseback rider? a/“figure that says more than anything else! now, i want to ride that stallion! " b/my daddy shook his head. "paul only rides horses he knows. ” c/? i glanced over at the other rider. the fellow was older than i, and had the weight of a man on him. d/a man out of alabama, man name of ray sutcliffe, told my daddy i was such a good rider, he wanted me to ride some races for him.