30 pts johnna is cooking a roast that says, "cook to 160°f." what is the celsius equivalent of this temperature? a) 65° b) 71° c) 81° d) 91°

You can use this equation to convert from Fahrenheit to Celsius:

C=(F-32)*(5/9)
C=Celsius degrees 
F=Fahrenheit degrees

Just plug in 160 for F and solve for C
C=(160-32)*(5/9)
C=128*(5/9)
C=71.11° repeating

Hope this helps