A number cube has 3 even numbers. Each even number has a theoretical probability of 1/6. In 60 rolls, an even number could come up ten times. Since there are 3 even numbers, the total predicted value is 30. So 20 is a low prediction.
Y=v(initial)*t+1/2at^2 since the velocity is zero at the maximum height then we get y=1/2at^2 a is just acceleration due to gravity so a=g which is 9.8 m/s^2. so y=1/2gt^2.