What is the angle in degrees w. r.t. the vertical of the photoresist if it is given a perfect exposure (bright areas are above clearing dose, and no photons hit areas that are supposed to be dark). the photoresist is 1.4 microns high, and it is given a 100% over development. the exposed resist is removed in the developer at 156 nm/s and the unexposed resist is removed in the developer at 0.23 nm/s. (two significant figures, fixed point notation, assume resist height is 1.4 microns)

To save energy, the air supply to a 2000 ft office has been shut off overnight and the room temperature has dropped to 40°f. in the morning, the thermostat is reset to 70°f and warm air at 120 f begins to flov in at 200ft'/min. the air is well mixed within the room, and an equal mass flow of air at room temperature (changing with time) is withdrawn through a return duct. the air pressure is nearly 1 atm everywhere. ignoring heat transfer with the surroundings and kinetic and potential energy effects, estimate how long it takes for the room temperature to reach 70°f. plot the room temperature as a function of time.