Which of the following is true about sorting functions? A. The most optimal partitioning policy for quicksort on an array we know nothing about would be selecting a random element in the array.
B. The fastest possible comparison sort has a worst case no better than O(n log n)
C. Heapsort is usually best when you need a stable sort.
D. Sorting an already sorted array of size n with quicksort takes O(n log n) time.
E. When sorting elements that are expensive to copy, it is generally best to use merge sort.
F. None of the above statements is true.

5.a fishing rod is formed from a composite material of 0.5 kg of glass fibers embedded in a matrix of 0.5 kg of epoxy resin. the glass fibers are assumed to be long, continuous and unidirectional. to achieve a greater stiffness it is proposed to use a different composite that is comprised of long continuous carbon fibers that will be embedded in a matrix of 0.5 kg of epoxy resin. if the modulus of elasticity of the carbon fiber composite is 10% greater than the elastic modulus of the glass fiber composite, estimate the mass of carbon fibers that will be used to make the carbon fiber composite. assume the applied tensile stress is parallel to the direction of the long axis of the fibers. the epoxy resin, glass fiber, and carbon fiber have an elastic modulus of 5, 86, and 350 gpa respectively and a density of 1100, 2500, and 1800 respectively.