Consider h(u) = 6u + 2u4+4u7-6u Determine the intervals on which is concave down. Oh is concave down on: h is concave down nowhere. Determine the intervals on which is concave up. Oh is concave up on: h is concave up nowhere. Determine the value and location of any inflection point of f. Enter the solution in (u, (u)) form. If multiple solutions exist, use a comma-separated list to enter the solutions. h has an inflection point at: Oh has no inflection point.