Me asap to do the math if a circle has an area of 25π mm², then what will the area be if the radius is increased by 3 mm? *\

A = pi*(8 mm)^2 = 64*pi mm^2

Step-by-step explanation:

The formula for the area of a circle is A = pi*r^2, where r is the radius.  Thus, r^2 = (25pi) / pi, or 25, and r = 5 mm.

If we increase this radius by 3 mm, we get the new radius 8 mm.  The area of the new circle will thus be A = pi*r^2, or, in this particular case,

A = pi*(8 mm)^2 = 64*pi mm^2.

the value of v.w= -12.

step-by-step explanation:

we are given three vector r,v and w as:

r = < 5, -5, -2> ; v = < 2, -8, -8> ; w = < -2, 6, -5>

we know that r,v and w could also be represented as:

r=5i-5j-2k

v=2i-8j-8k

and w= -2i+6j-5k

where i,j and k are the unit vectors of x,y and z-axis respectively.

also we know that it has the following property:

i.i=1 ; j.j=1; k.k=1

and i.=j.i=i.k=k.i=j.k=k.j=0

i.e. when we multiply two vectors or we find it's dot product we need to only multiply the components of x coordinates with each other; y with each other and z with each other.

hence, v.w= (2i-8j- -2i+6j-5k)

                  = 2×(-2)+(-8)×(6)+(-8)×(-5)

                  = -4-48+40

                  = -12

hence, v.w= -12