B - check your answers and present the solution
Answer:

Step-by-step explanation:

First, we expand the equation using the distributive rule:

Hence, 
Simplify: 
Add like terms:

Subtract 13 from both sides: 
Divide both sides by -8:

Answer:
16
Step-by-step explanation:
113-17= 96
96/6= 16
Answer:
no I do not agree, Because it doesn't make since
To Find :
Position vector at time
and
.
Solution :
r (t) = 2 (t −7)i + 12t j
Putting t = 5 s and t = 8 s, we get :
r(5) = 2( -2 )i + 60j
r(5) = -4i + 60j
r(8) = 2i + 96j
Now, to find speed differentiating the r(t) w.r.t t :

Hence, this is the required solution.