The weekly demand for a product approximately has a normal distribution with mean 1,000 and standard deviation 200. The current on hand inventory is 2,200 and no deliveries will be occurring in the next two weeks. Assuming that the demands in different weeks are independent, (a) what is the probability that the demand in each of the next 2 weeks is less than 1,100? (b) what is the probability that the total of the demands in the next 2 weeks exceeds 2,200?

Solid State Devices Electronics- Solid State Devices in a circuit Doping- Mixing a small amount of an impurity with a silicone (.7 volt drop) germanium (.3 Volt drop) structure N-type- 5 Electrons (one has nothing to bond to) P-type- 3 Electrons (positive) P-type + N-type = Diode Diodes… Are the simplest possible semi-conductor Allow current to flow in one direction but not the other o Wont flow if negative charge is on the P-type Types of diodes Zener Diode- has a reverse current bias up to a certain voltage (used in regulators) Rectifier Bridge- Used to turn AC current to DC o Contains 6 diodes Clamping Diode- Used to control damaging high voltage spikes o Installed across coil windings Photo Diode- Allows conduction in forward bias when exposed to light o Resistance decreases as light increases Transistor Base Collector Emitter PNP- Base needs Negative charge NPN- Base needs positive charge o Arrow always points towards the N-type Metal Oxides Field effect transistor (MOSFET) Low current = More efficient Very sensitive to high voltage source Silicon Chips- Can hold thousands of transistors Thermistor NCT- Decreases Resistance as temperature increases PCT- Increases resistance as temperature increases