(c) Mendeleev was convinced of the importance of arranging elements in the periodic table in accordance with trends therefore he questioned the accuracy of the atomic masses of several elements. One place you can see this is in the fourth period; identify the elements involved, and explain why he questioned the atomic masses. ​

Y= 4/5 x + 24
To find the rate of change you find the difference in each of the numbers on the graph. For example, 36-32 is 4. So 28-4 is 24 and that would be the next number down. It would also match x to be 0 because since the rate of change for x was 5, if you subtract 5 from 5 you get 0. So from this we know that the coordinates would be 0,5.
From this info, the slope would be 4/5 and the y intercept or initial value would be 24