The height of the small rectangle is the same as that of the second group (2 points)

As shown in the figure,

(2)25÷0. 1=250; (2 points)

Because the scores of students 125 and 126 are in the fourth group, the median of these scores falls in the fourth group. (2 points)

(3) 5000× (0.1+0.2) =1500 (2 points)

So the answer is 0.1; 250; Fourth; 1500.