The answer is 72
trust me
D = 5/6 sqrt(h)
7 = 5/6 sqrt(h)
42/5 = sqrt(h)
h = (42/5)^2 = 1,764/25 = 70.56
The height of the mast is 70.56 miles
From A :50/hour. *x(hour)
From B : 30/hour *x(hour)
50 *x +30 *x =400
80 *x=400
x=5(hour)
Then the train from A will make 50 *5=250 miles
(These is fisik)
The answer is 7/10 because the even values are 2,4,6, and the others are 7,8,9,10. Added together, it adds up to 7/10
