I need help with this ASAP

Check all that apply. f is a function. f is a one-to-one function. c is a function. c is a one-to-one function.

Maria found the least common multiple of 6 and 15. her work is shown below. multiples of 6: 6, 12, 18, 24, 30, 36, 42, 48, 54, 60, . . multiples of 15: 15, 30, 45, 60, . . the least common multiple is 60. what is maria's error?

The base of the rectangle pyramid is 13 inches long and 12 inches wide the height of the pyramid is 18 inches . what is the volume of the pyramid ?