1. Give a geometric description of the set of points in space whose coordinates satisfy the given pair of equations. x2 + y2 = 16, z = 2 Choose the correct description. A. The circle with center (0, 0, 2) and radius 4, parallel to the xy-plane. B. The line through (4, 4, 2), parallel to the z-axis. C. The line that passes through the points (4, 0, 2) and (0, 4, 2).D. The circle with center (4, 4, 0) and radius 2, parallel to the xy-plane.2. For the points P1(-5, 3, 1) and P2(5, l, 0), find the direction of P1P2rightarrow and the midpoint of line segment P1P2. 3. Find the following for the vectors u = -5i + 4j + root7 k and v = 5i - 4 j - root7 k. a. v·u, |v|, and |u| b. the cosine of the angle between v and u c. the scalar component of u in the direction of v d. the vector projvu v·u 4. Find a vector of magnitude 3 in the direction of v = 12i - 9 k.

I've been working on this for a few days and i just don't understand, it's due in a few hours. you.the direction of a vector is defined as the angle of the vector in relation to a horizontal line. as a standard, this angle is measured counterclockwise from the positive x-axis. the direction or angle of v in the diagram is α.part a: how can you use trigonometric ratios to calculate the direction α of a general vector v = < x, y> similar to the diagram? part bsuppose that vector v lies in quadrant ii, quadrant iii, or quadrant iv. how can you use trigonometric ratios to calculate the direction (i.e., angle) of the vector in each of these quadrants with respect to the positive x-axis? the angle between the vector and the positive x-axis will be greater than 90 degrees in each case.part cnow try a numerical problem. what is the direction of the vector w = < -1, 6 > ?