Suppose your professor handed you a test tube with 3 ml of an e. coli culture in it and told you to make a 10-3 dilution of the entire culture volume with water. what would your final volume (v2) of the dilution need to be in order to get this dilution? hints: use v1d1 =v2d2 and remember to use the d1 of a stock (undiluted sample)

Consider a 1000 w iron whose base plate is made of 0.5 cm thick aluminum alloy 2024-t6 (ρ = 2770 kg/m3 and cp = 875 j/kg°c). the base plate has a surface area of 0.03 m2. initially, the iron is in thermal equilibrium with the ambient air at 22°c. assuming 90% of the heat generated in the resistance wires is transferred to the plate, determine the minimum time needed for the plate temperature to reach 200°c.