A chunk o’ Gallium Nitride is doped p-type (8E19 cm-3), but the p-type doping ionization efficiency is 4%. (note: this will the doping) What is the electron concentration, Ne? If the electron effective mass is 0.20mo, find the hole effective mass, in terms of mo.    

For our chunk o’ GaN in Question 1 Find the average time between collisions for holes. For a 6 cm long sample with A=1cm, if a voltage of 25V is placed across opposite surfaces, what will be the current density? For this same current (from B) is used in a Hall effect measurement and the Hall electric field was found to be 87.5 V/cm, what magnetic field B was used?

Do the findings of the “Diabetes and Fat” article support or reject the idea that obesity can predispose someone to develop Diabetes?

All of the following are true about Alzheimer’s disease except…

Ectopic pregnancies can be life threatening.  

Phosphodiesterase prolongs the action of cGMP  

Breast cancer grows by expansion

Osteoporosis is an increase in bone density.

Identify the bony structure indicated by the arrow.  

Identify the part of the gastrointestinal tract indicated by the arrow.