Dayana picked apples for 2 hours. she picked 28 apples in the first hour, and at the end of two hours, she had 49.how many apples did she pick during the second hour?

49-28=21

she picked 21 apples in the second hour

To answer this item, we first determine the volume of the inverted cone thru the equation,
                                       V = Bh/3
where B is the area of the base and h is the height. 
                                   V = (π)(3 in)²(4 in) / 3
                                        V = 37.68 in³
Then, divide the rate of the water dripping by the number of house,
                                                n = (37.68 in³)/12 in³/min
                                                   n = 3.14 mins