A cell membrane separates three species of ions (Na+, Cl-, K+). The Nernst potentials are: VNa = 50 mV, Vcl = -60 mV, VK = -100 mV. The membrane potential is held to be constant at Vm = -70 mV. Given that gNa = 1 pS, gcl = 2 pS, and gK = 4 pS:(a) Calculate the electrical current carried by each of the ion species.(b) Indicate the direction that each of the species is transported across the membrane.

Three different objects, all with different masses, are initially at rest at the bottom of a set of steps. each step is of uniform height . the mass of each object is a multiple of the base mass : object 1 has mass 4..00m , object 2 has mass 1..96m , and object 3 has mass . when the objects are at the bottom of the steps, define the total gravitational potential energy of the three-object system to be zero. if the objects are then relocated as shown, what is the new total potential energy of the system? each answer requires the numerical coefficient to an algebraic expression. each algebraic expression is given using some combination of the variables , , and , where is the acceleration due to gravity. enter only the numerical coefficient. (example: if the answer is 1..23mgd , just enter 1.23)

Agroup of monkeys is trying to cross the river in a rowboat. the maximum buoyant force on the rowboat is 2,000 n. the weight of the rowboat is 1,000 n. each monkey has a weight of 150 n. how many monkeys can safely cross in the rowboat at one time? explain your reasoning, including any calculations you used to find the answer.

You can estimate the degree to which a bond between two atoms is ionic or covalent by calculating the