Basically apply your radius and slant height to the formula to find the surface area of a cone which is S=3.14r^2+3.14rl
 
        
        
        
The magnification is 0.54
Given,
The distance between object and concave lens, u = -21 cm
Focal length of the concave lens, f = -25 cm
Let m be the magnification.
m = v/u
Here v is the position of image.
We have to find v first.
By using lens equation we can determine v.
That is,
1/f = 1/v – 1/u
So,
- (1/25) = 1/v – (-1/21)
- (1/25) = 1/v + 1/21
1/v = - (1/25) – 1/21
1/v = (-25 – 21) / (21 x 25)
1/v = - (46/525)
Therefore v = - (525/46)
    v = -11.41 cm
Now we have to find magnification, m.
m = v/u
    = (-11.41) / (-21)
    = 0.54
Here magnification is 0.54
Learn more about concave lens here: brainly.com/question/12944945
#SPJ4
 
        
             
        
        
        
Not true, at least not always. When we are talking about an isosceles triangle there will be two equal altitudes and one is different. In case of a regular triangle all the other three altitudes have equal length! :)
        
             
        
        
        
Answer:
$24.50
Step-by-step explanation:
So first we have to find what 2/5 of 35 is. So 35*2/5=14. So she has sold 14 balloon animals so far. So now we multiply 14 by 1.75 and we get 24.5.