Answer:
The instantaneous velocity at
is
.
Step-by-step explanation:
We have the position as the function

As we know that the velocity is the rate of change of position over time, so it is basically the derivative of the function.
so finding the derivate of 
∴ 
The instantaneous velocity at 

Therefore, the instantaneous velocity at
is
.
Please note that the negative value indicates the direction of movement, in this case, it would be backward.
Answer:
4 questions
Step-by-step explanation:
90% is the same as multiplying a number by 0.9. Let's say the number of questions on the quiz is x. This means the amount she got right was 0.9x. We are given this is 36, so we can set them equal and simplify:
0.9x = 36
x = 40
She must have gotten 40 - 36, or 4 questions wrong.
50 =2×5×5
125=5×5×5
Hoghest common factor = 5×5
=25