thermometer c = new centigrade(); thermometer f = new fahrenheit(); displayer cd = new displayer("centigrade"); displayer fd = new displayer("fahrenheit"); prompter cp = new prompter("enter centigrade value"); prompter fp = new prompter("enter fahrenheit value"); show sc = new show(c,cd); show sf = new show(f,fd); update uc = new update(c,cp); update uf = new update(f,fp);