If an isotope's half life is 2 months, and it starts with 240 grams. How many half life's does it take to only have 15 grams left? A. 2
B. 4
C. 6

Dr. bad has developed a way to damage the atp-binding cassette transporter (abc transporter) on a cell. the cell's abc transporter can no longer bind and use atp when it's transporting substances. which of the following statements best describes how this damage would effect the transport of substances in the affected cell? (choice a) substances at a low concentration outside the cell would be more rapidly transported into the cell, where there is a high concentration. (choice b) substances at a high concentration outside the cell would not be transported into the cell, where there is a low concentration. (choice c) equilibrium would be established between all substances inside and outside of the cell. (choice d) substances at a low concentration outside the cell would not be transported into the cell, where there is a high concentration.

Many kangaroo rats live in the sonoran desert of the southwestern united states. they have a variety of adaptations for living in the desert. under which circumstance would the kangaroo rats of the sonoran desert be most likely to develop new adaptations by natural selection?

Explain how the political influence of african americans leaders became weaker.