1)How do you distinguish between positive and negative logic system? Prove that an OR gate in a positive logic System is an AND gate in a negative logic system. 2)Give a brief statement that would help one remember the truth table of AND ,NAND, OR, NOR, EX-OR and EX -NOR logic gate functions ,irrespective of the number of input used. ​

Consider a 1.2 meter high and 2 meter wide glass window whose thickness is 6 mm and thermal conductivity is 0.78 w/m °c. the room temperature is maintained at 24 °c, while the outdoor temperature is -5 °c. the convective heat transfer coefficients on the inner and outer surfaces of the window are 10 w/m2 °c and 25 w/m2 °c respectively. (a) draw the thermal resistance network, etermine the steady rate of heat transfer t e glass window (c) determine the temperature of the inner surface of the window