A man travelled a distance of 28 km in 8 h. He travelled partly by foot at a speed of 2 km/h and partly on bicycle at a speed of 6 km/h. What was the distance (in km) travelled on foot?
An apple tree is taller than a lemon tree. A papaya tree is shorter than a palm tree. A mango tree is shorter than the papaya tree but taller than the apple tree. Which is the tallest tree?