Answer:
1. isosceles because two of the sides are equal
2. right because there is a right angle
Step-by-step explanation:
yo sup??
the sum of trails taken should be less than 25 miles
Black bear=B
Eagle Ridge=E
Doe Run=D
(btw names sound cool XD)
we will now try different combinations
B+E=7 1/2 ++ 10 1/4 which is clearly less than 25
B+D=7 1/2 + 8 3/4 which also less than 25
E+D=10 1/4 + 8 3/4 which is also less than 25
B+D+E=7 1/2 + 10 1/4 + 8 3/4 which is greater than 25
Therefore only the 1st,2nd and 3rd case are possible
Hope this helps.
Step-by-step explanation:

The bottom rectangle is 52 ft by 27 ft.
The top rectangle is 30 ft by 17 ft (calculated as 57 ft - 27 ft - 13 ft = 17 ft).
The connector rectangle is 13 ft by 9 ft (calculated as 30 ft - 21 ft = 9 ft).
total area = 52 ft * 27 ft + 30 ft * 17 ft + 13 ft * 9 ft
total area = 1404 ft^2 + 510 ft^2 + 117 ft^2
total area = 2031 ft^2
weight = 2031 ft^2 * 12 lb/ft^2
weight = 24,372 lb
1/2(12+8)=10 Answer is 12