E+10 is equivalent to 10^10 so, 9e+10 is equivalent to 9*10^10. 300,000^2 is 90000000000 square miles, where as the US has 4000000. Therefore, if the national forest were as large as the environmentalist wants them to be, the forest would be larger than the US, which is IMPOSSIBLE !!! As a result, this goal is not reasonable 
        
             
        
        
        
Its D 15+15+15= 45  so there for it will be 45                       
                                                             
        
             
        
        
        
If a line's slope is 

, the slope of the perpendicular line is 

in this case, the given line has a slope 4, which is 4/1, so the perpendicular line has a slope/gradient 
 
 
        
        
        
I believe the answer is $48 because 6 * 2 is 12 and 12 * 2 is 24 and 24 * 2 is 48, thus 48$. Please feel free to check my work, though.