The cash flows for two alternatives X and Y are shown in the table displayed here. Year: 0 1 2 3 4 5
Alternative X: -$3,000 900 900 900 900 1,300
Alternative Y: -$5,000 1,400 1,400 1,400 1,400 2,100
Write an equation using appropriate compound-interest factors that could be used to solve for the incremental rate of return (ΔIRR) associated with these two alternatives. Do NOT solve this equation for ΔIRR.

Awall of 0.5m thickness is to be constructed from a material which has average thermal conductivity of 1.4 w/mk. the wall is to be insulated with a material having an average thermal conductivity of 0.35 w/mk so that heat loss per square meter shall not exceed 1450 w. assume inner wall surface temperature of 1200°c and outer surface temperature of the insulation to be 15°c. calculate the thickness of insulation required.