Please help with answering these math questions. The answer MUST be one of the multiple choices. Please take your time in doing the work, the arithmetic has to be correct and so does the final answer. I really need help in getting these problems right, thank you!

Question 12(Multiple Choice Worth 2 points) (06.03) If a spring is oscillating (moving) according to the velocity equation v(t) = cos(t) (in ft/s), then what is its displacement over its first 2Tr seconds of travel? O 2 ft Ooft O 3 ft O 4 ftQuestion 4(Multiple Choice Worth 2 points) (06.02) Which of the following statements is true? The volume of the solid formed by rotating the region bounded by the graph of y = x2, x = 3, y = 0 around the y-axis is I. n x2 dx I1. It (3- vy) dy Ill. It (9-y)dy O I only O Ill only O II only O I and IIIQuestion 3(Multiple Choice Worth 2 points) (06.01) Find the area of the region bounded by the graphs of y = x, y = -x + 4, and y = 0. 0 4 O 2 0 8 O None of these