(a) for three p-n junction diode samples a, b, and c, acceptor and donor carrier concentrations are the same 1015/cm3 and 1018 /cm3, respectively. band gaps for the three samples a, b, and c are 0.6 ev, 1.4 ev, and 1.9 ev, while the electron and hole effective masses of density of states are the same in all the three materials, me = 0.05m0 and mh = 0.2m0, where is the electron mass in free space. find the built-in potentials for these three devices at t = 300 k. comment on the comparison of estimated built-in potentials.

I'm kinda lost ! 1. when marilyn takes her pet dog for a walk, the dog walks at a veryconsistent pace of 0.55 m/s. draw a position-time graph to representmarilyn's dog walking the 19.8 m distance from the front of her house tothe nearest fire hydrant.2. both car a and car bleave school when a stopwatch reads zero. car atravels at a constant 75 km/h, and car b travels at a constant 85 km/h.a) draw a position-time graph showing the motion of both cars. howfar are the two cars from school when the stopwatch reads 2 hrs? calculate the distances and show them on your graph.b) both cars passed a gas station 120 km from the school. when dideach car pass the gas station? calculate the times and show themon your graph.3. the figure below shows the position-time graph showing a shopper'smovement up and down the aisle at a store.a) write a story describing the shopper's movements at the store.b) when does the shopper have a position of 6 m? c) how much time passes between when the shopper enters the aisleand when he gets to a position of 12 m? what is the shopper's averagevelocity between 37 s and 46 s?

What is the measurement of how fast an object moves relative to a reference point?

A100-watt light bulb illuminates a solar cell. the electricity from the solar cell operates a water pump that delivers 1 watt of power. what is the efficiency of the system?