Answer 1

CH₃NH₂+COCl₂ →CH₃N=C=O+2HCl
    (41)       (99)         (57)

% Atom Economy =`"Molecular weight of the product"/"Total molecular weight of reactant"xx100`

`(57xx100)/(41+99)`

= 43.86%
CH₃NH₂ = 12+13+14+2
= 41
COCl₂=12+16+2X35.5
= 99
CH₃ = C = O = 12+3+14+16
= 57