Def eval(self, env): """ >>> from reader import read >>> new_env = global_env. copy() >>> new_env. update({'a': Number(1), 'b': Number(2)}) >>> add = CallExpr(Name('add'), [Literal(3), Name('a')]) >>> add. eval(new_env) Number(4) >>> new_env['a'] = Number(5) >>> add. eval(new_env) Number(8)

The y form of iron is known as: a) ferrite b) cementite c) perlite d) austenite

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.

Acertain flow of air (at stp) has a velocity distribution given by v i (in ft/s). if this flow is going through a 4 ft square area in the yz-plane (centered at the origin), what is the mass flow rate (in lbm/s)?