Answer: cost of plastic = $168,000
excess cost = $3000
Explanation: This can be done as follows :-
cost of plastic = (standard quantity per * (standard price * ( no. of helmet)
should been helmet) per kg of plastic)
incurred
= (0.6) * (8) * (35,000)
= $168,000
so the extra cost incurred is $3000 that is $171,000 - $168,000 .