Technician A says that most crankshafts can be reground to be 0.010, 0.020, or 0.030 inch undersize. Technician B says that most engine bearings are constructed with an aluminum shell for strength and are covered with a tin-lead alloy. Which technician is correct?

The gene that causes sickle-cell disease is present in a higher percentage of residents of sub-saharan africa than among those of african descent living in the united states. even though this gene causes sickle-cell disease, it also provides some protection from malaria, a serious disease that is widespread in sub-saharan africa but absent in the united states. discuss an evolutionary process that could account for the different percentages of the sickle-cell gene among residents of the two regions.

How many copies of each chromosomes should be present in each of the 4 final haploid versions of gamete?

What type of competition exsist between two species. turtles and fish