Answer:
C
Step-by-step explanation:
A, B and D are all only a few digits long and can be expressed as the ratio of two integers, where at least one is even:
A = -6/16 = -3/8, so it's rational
B = 7.0398 = 35199/5000, so it's rational
D = 6,907 = 13814/2, therefore rational
C, on the other hand is irrational. 
If we simplify the surd √8, we get 2√2. The 2's on the top and bottom can now cancel out, giving us √2, which is irrational. [There's a proof but it's kinda long].
 
        
             
        
        
        
The minimum distance will be along a perpendicular line to the river that passes through the point (7,5)
4x+3y=12
3y=-4x+12
y=-4x/3+12/3
So a line perpendicular to the bank will be:
y=3x/4+b, and we need it to pass through (7,5) so
5=3(7)/4+b
5=21/4+b
20/4-21/4=b
-1/4=b so the perpendicular line is:
y=3x/4-1/4
So now we want to know the point where this perpendicular line meets with the river bank.  When it does y=y so we can say:
(3x-1)/4=(-4x+12)/3  cross multiply
3(3x-1)=4(-4x+12)
9x-3=-16x+48
25x=51
x=51/25
x=2.04
y=(3x-1)/4
y=(3*2.04-1)/4
y=1.28
So now that we know the point on the river that is closest to Avery we can calculate his distance from that point...
d^2=(x2-x1)^2+(y2-y1)^2
d^2=(7-2.04)^2+(5-1.28)^2
d^2=38.44
d=√38.44
d=6.2 units
Since he can run at 10 uph...
t=d/v
t=6.2/10
t=0.62 hours  (37 min 12 sec)
So it will take him 0.62 hours or 37 minutes and 12 seconds for him to reach the river.
        
             
        
        
        
Solution:
we are given that 
A school director Must randomly select 6 teachers to participate in a training session there are 30 teachers at the schoo. The order of selection does not matter.
As we know
6 teacheras can be selected out of 30 teacher in  ways.
 ways.

Hence the required number of ways is 593775.
 
        
             
        
        
        
Answer:
The first blank: not equal 
The 2nd blank: not right triangle (it's acute triangle)
The 3rd blank: equal
The 4th blank: it's right triangle
Step-by-step explanation:
 4^2 = 3^2 + 3^2
<=> 16 = 9 + 9
<=> 16 = 18 ( nonsense)
so triangle LKJ is not right triangle 
 5^2 = 4^2 + 3^2
<=> 25 = 16 + 9 
<=> 25 = 25 ( make sense)
so triangle ABC is right triangle
Done!! :))