Maria is wrong because they have completed 1/2.
Step-by-step explanation:
At the top of the Ferris wheel,the ride is 1/2 done. All that is left is to go down,which is the other half. Maria is wrong in saying they are 1/4 done,that is a quarter,not half.
 
        
             
        
        
        
Answer:
The radius is increased by 1.2599 times the original size.
Step-by-step explanation:
The volume is 3 dimensional whereas the radius is one dimensional.
 Therefore the factor for the  radius will be the cube root of the factor for the volume.
So the radius is increased by 1.2599.
 
        
             
        
        
        
Answer:
10^-8
Step-by-step explanation:
 
        
             
        
        
        
Answer:x=-8
Step-by-step explanation:subtract 21 from both sides then simplify 31-21 to -8
 
        
             
        
        
        
In this type of calculations, we decompose 13 by checking the lowest powers of the base, that is 40. for example we check 40^2, or 40^3 and compare it to 85
Notice
40*40*40=64,000
so we check how many time does 85 fit into 64,000:
64,000/85=752.94
85*753=64,005;       64000-64,005=-5
this means that 

thus

Answer: 10 (mod85)
Remark, the set of all solutions is:
{......-75, 10, 95, .....}, that is 85k +10