A hollow box beam ABC is supported at end A by a 20 mm diameter pin that passes through the beam and its supporting pedestals. (a) Calculate the average shear stress in the pin due to a load P equal to 10 KN (b) Calculate the average bearing stress between the pin and the box beam if the wall thickness of the beam is equal to 12 mm. (c) Calculate the normal stress in the pedestal at support A. Pedestal height is 30 cm, width is 15cm and thickness is 15mm.

An external consultant recommends that a plant installs a bank of capacitors for power factor correction. this will reduce the peak electrical demand charges by an average of 93 kw every month. the plant current pays $13 per kw in peak demand charges. the capacitor bank will include 223 kw of fixed capacitors, and 183 of variable capacitors. the fixed capacitors cost $59 per kw, and the variable capacitors will cost $65 per kw. the consultant charges 21% of the equipment costs to install the capacitors. because this project will reduce the demand for the electric utility, they are prepared to provide a one-time rebate of $42 per kw of reduced demand. what is the simple payback period for this project (in years)?