Michelle puts the 12 tiles shown below in a bag. Michelle takes one tile from the bag without looking. What is the probability that Michelle will pick a tile with exactly four sides?

Explain the difference laminar and turbulent flow. explain it with the shear stress and the velocity profiles.

Different types of steels contain different elements that alter the characteristics of the steel. for each of the following elements, explain what the element does when alloyed with steel.

A-mn has a cubic structure with a0 0.8931 nm and a density of 7.47 g/cm3. b-mn has a different cubic structure, with a0 0.6326 nm and a density of 7.26 g/cm3. the atomic weight of manganese is 54.938 g/mol and the atomic radius is 0.112 nm. determine the percent volume change that would occur if a-mn transforms to b-mn.