If x is doubled and y is halved, the new value of f is

Question

Let f(x,y) = xⁿy^m = P. If x is doubled and y is halved, the new value of f is                                                                                     

      (a) 2^n-m P                                                             (b) 2^m-n P

      (c) 2(n-m)P                                                         (d) 2(m-n)P

Answer 1

Option :               A