Can someone answer these questions for me? (Questions are in the picture)

Is this a polynomial function? i need to know asap

If a 36 inch yardstick casts a 21 foot shadow, how tall is a building whose shadow is 168 feet? what is the scale factor

The description below represents function a and the table represents function b: function a the function is 5 more than 3 times x. function b x y −1 2 0 5 1 8 which statement is correct about the slope and y-intercept of the two functions? (1 point) their slopes are equal but y-intercepts are not equal. their slopes are not equal but y-intercepts are equal. both slopes and y intercepts are equal. neither slopes nor y-intercepts are equal.