Please answer this I need help.

Here I will explain this for you

Step-by-step explanation:

For the first questions 21-28 all you have to do is plug in 11 for s and plug in 8 for v. So then you would solve for the answers and that's all. For 29-34 a little hint is for you todo everything that is in () first than [] then multiply that answer by the outside number. For 35 and 36 plug in what you know form what it tells you into the formula. B=4 and H=9 for example plug that into the formula that they give which is bh/3 and you would get your answer. But always try to do the square root first if they give you that in the number. Also, don't forget to label your answer (cm) for the last to questions.