Which expressions are equivalent to j+j+2k

select all that apply:

2jk
2(j+j+k)
none of the above

Which of the following best describes the graph below? + + 2 + 3 + 4 1 o a. it is not a function. o b. it is a one-to-one function. o c. it is a many-to-one function. o d. it is a function, but it is not one-to-one.