Answer the following questions for the functionf(x) = x \sqrt{x^2 + 25}defined on the interval [ -7, 5 ] .a. f(x) is concave down on the interval tob. f(x) is concave up on the interval toc. the inflection point for this function is at x=d. the minimum for this function occurs at x=e. the maximum for this function occurs at x =