What is the cost of 3.5kg of pork at $7.99/kg?

It is given in the question that cost of pork is $7.99/kg.

It means cost of 1 kg pork is $7.99.

Cost of 2 kg of pork is

And cost of 3 kg of pork is

Therefore cost of 3.5 kg of pork is

let f(x) = 6x^2 + 5 and g(x) = 3x-5.

f(g(x))=f(3x-5)=6(3x-5)²+5=6(9x²-30x+25)-5

=54x²-180x+150-5=54x²-180x+145

again

f(g(7))=54×7²-180×7+145

=1531 is your answer