a) 4

b) 3

c) 2.5

d) 1

correct answer is: d) 1
Formula use: \left(a+b\right)^3=a^3+3a^2b+3ab^2+b^3

Explanation

Here, given expression is :
27x^3+108x^2y+144xy^2+64y^3
\rightarrow\left(3x\right)^3+3.\left(3x\right)^2.4y+3.3x.\left(4y\right)^2+\left(4y\right)^3
\rightarrow\left(3x+4y\right)^3
Now, put the value of ‘x’ and ‘y’, we get :
\rightarrow\{\left(3\times3\right)+\left(4\times-2\right)\}^3
\rightarrow\{9+\left(-8\right)\}^3
\rightarrow\left(9-8\right)^3
\rightarrow\left(1\right)^3
\therefore 1
Ans: 1.