Which one of the following statements is true? A -If f ′′(x) > 0 on the interval (a, b), then f is concave up on the interval (a, b). B -If f ′′(c) = 0, then x = c is an inflection point on the graph of f(x). C- If f is continuous on a closed interval [a, b], then f attains an absolute maximum value and f attains an absolute minimum inside the interval [a, b]. D- None of these are true.

Astock has a 25% probability of increasing by $10 and a 75% probability of decreasing by $5. what is the stocks expected increase or decrease?

2and 3 are angles. complementary vertical congruent supplementary

The monthly texting plan of all star cell is $11 per month and $0.25 per text. the monthly texting plan of top line cell is $14 per month and $0.15 per text. a student wants to set up a system of equations to find the number of texts for which the total monthly cost of the two companies is the same. he uses the variables x and y. he lets y represent the total monthly cost. what will x represent? x = number of texts x = cost of the total number of texts x = total monthly cost x = cost of each text