Answer
See answer below.
Work Step by Step
a) Reactants: $C_4H_9O_6$, $153.11\ g/mol$
Product: $98.06\ g/mol$
Atom economy: $98.06/153.11\times100\%=64.0\%$
b) Number of moles of butene:
$1000\ g\div 57.12\ g/mol=17.51\ mol$
Mass of maleic anhydride:
$17.51\ mol\times 98.06\ g/mol=1716.9\ g$
Percent yield:
$1200/1716.9\times100\%=70.0\%$
