The diagram shows a trapezium with a top side of 12 cm, a left side of 16 cm (with a right angle at the bottom left), a slant right side of 20 cm and a bottom side of 24 cm. NOT TO SCALE. Two students try to calculate the area of the trapezium in different ways. First student: 16 + 12 + 20 + 24. Second student: \(16 \times 12 + \frac{1}{2} \times 12 \times 16\). Show whether each student's calculation is correct or not correct.