Dana cannot taste any difference between Coke (c) and Pepsi (p) and so she views one bottle of each as perfect substitutes.Which utility functions might reflects Dana's preference? (The answers have more than 1 answers and you must choose all of correct options)

a. U(c,p)=c+p

b. U(c,p)=sqrt(c+p)

c. U(c,p)=2c+2p

d. U(c,p)=sqrt(2c+2p)

e. U(c,p)=2c+p

f. U(c,p)= sqrt(2c+p)

g. U(c,p)= cp

h. U(c,p)= sqrt(cp)