What is the y-intercept of the 1st graph? What is the y-intercept of the 2nd graph? Are the y-intercepts the same?

Bob the builder is making 480kg of cement mix. this is made by cement, sand and gravel in the ratio 1: 3: 4

Azul has 4 green picks and no orange picks.you add orange picks so that there are 2 orange picks for every 1 green pick.how many picks are there now.

If you were constructing a triangular frame, and you had wood in the length of 4inches, 4 inches, and 7 inches, would it make a triangle? would you be able to create a frame from these pieces of wood?