2. The probability that a randomly selected Grade 11 student will play one game of Candy Crush in less than 3 minutes is
a) 0.3551
b) 0.3085
c) 0.2674
d) 0.1915
3. The probability that a randomly-selected grade 11 student will take between 2 and 4.5 minutes to play Candy​

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

you didn't give me the choices, so i will just give you the graph so you can look at your choices and choose the right one.

3 3 6, because in every triangle the longer side is always shorter than the sum of the other two