By increasing stress, this rod (from 1a) eventually fractured. Estimate the maximum stress at crack tip. It is known that fracture occurs by propagation of an elliptically shaped surface crack of length 0.3 mm. This crack has a tip radius of curvature of 0.003 mm. Assuming that the applied stress is the result of the load of 47,124 N. Answer in terms of GPa (do not include units in answer)

Determine the time of the day and month of the year at which the peak sensible cooling load occurs for a top floor, north-eastern corner room of an office building in durban for the following conditions: floor area: 8 x 8 x 3 m east and north walls: 115 mm face brick (outside), 20 mm air space, 115 mm ordinary brick (inside) with 15 mm plaster roof construction: suspended plasterboard ceiling, 450 mm air space, 150 mm concrete, 75mm screed, waterproofing no heat transfer across other surfaces window area 3x 1,5 m high in north wall only. ordinary glass with venetian blinds. lights and occupants : from 07: 00 to 18: 00 average light density: 25 w/m2 number of occupants : 5 seated, light office work room temperature 24°c