10. Suppose a student drew a graph of each function described below. For which graphs should the student connect the points? Justify your answers. a) The cost of a custom-made T-shirt is a function of the number of letters on the T-shirt. b) The altitude of a plane is a function of the time it is in the air. c) The mass of a baby is a function of her age. d) The cube root of a real number is a function of the number.