all three pls

1. Determine whether the statement is true or false. Assume u, u, and w are non-zero vec- tors. [6pts] i) The cost of movie ticket is a scalar quantity. ii) If a and b are orthogonal vectors, then a . b = 0 iii) If u and u are orthogonal to w , then u is parallel to . iv) uxv = vxu v) If c is a real number, then | |cull = clu1) vi) For any vector a, then a x a = 0 2. Find an equation of the largest sphere with center (2, 4,5) that is contained in the first octant. [5pts] 3. Show that the equation x2 +y + 22 +8x-6y + 2z+17 = 0 represents a sphere. Indicate its center and radius. Also, describe its intersection with each of the coordinate planes.[8pts]