Meter is the best metric measurement.
        
             
        
        
        
Answer:
b. i think
Step-by-step explanation:
 
        
             
        
        
        
Answer:
Step-by-step explanation:
Here you go mate
Step 1
-(-2 + 9)  Equation/Question
Step 2
-(-2 + 9)  Simplify
-(-2 + 9)
Step 3
-(-2 + 9)  Solve by adding
-(7)
=-7
Answer
-7
 
        
             
        
        
        
As shown in the figure 
Height of helicopter above the ground=30 m
Distance from the base to the point where the person is standing=30 m
height of the person=2 m
Now the person cast the shadow of length x m.
Triangle ABC and triangle EDC are similar.
∵ ∠B= ∠D=90°
∠C is common.
 So by AA similarity ΔABC and ΔEDC are similar.
As we know when triangles are similar their sides are proportional.
AB/AD =BC/DC
Let DC=x meter
⇒
⇒5=\frac{30+x}{x}[/tex]
⇒5x=30+x
⇒4x = 30
⇒ x=30/4
⇒ x=7.5 meter
So length of shadow=7.5 meter
2. volume of a sphere of radius r is v (r) =
  =4/3π×3
=4/3π×3
        =4π
surface area of a sphere of radius r is 4π
b)  Ratio of derivative of volume of sphere to surface area of sphere=
              =1  [ incomplete question but you have written few words ]
 
        
             
        
        
        
Answer:
$45
Step-by-step explanation:
Here we need to calculate the income of this year. 
We know that a year has 52 weeks. And, our payed weeks are 51, they are, the 50 weeks we work plus the one week of paid-vacation. The remaining week does not give us income, as is unpaid. So our total year income is:
51 * $615 = $31,365
So, our surplus will be our income minus our expenses:
Surplus = $31,365 - $31,320 = $45
Our cash surplus is $45