Equation of the line joining the points R(-1,6) and S(5,5)
2.6 * 10^9
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1.3 * 10^2
2.6 / 1.3 = 2 and 10^9 / 10^2 = 10^7
so the answer is 2 * 10^7
The answer of your first question is the part (C)
The answer of your second question is also part (C)
The answer of your third question is part (b)