“If the unicorn is mythical, then it is immortal, but if it is not mythical, then it is a mortal mammal. If the unicorn is either immortal or a mammal, then it is horned. The unicorn is magical if it is horned.” Can you prove that the unicorn is (i) mythical? (ii) magical? or (iii) horned? (In each case give the reason for the conclusion you reach).