Explanation

In this question, "equally spaced" appears to indicate that the tick marks could represent integer spaces--so that k=3, for example--but they might not. The key to getting m is probably going to be figuring out the width between two tick marks.

Statement (1) gives us the value of k, which is 1 plus two tick marks. Ergo, the statement tells us that a tick mark equals . Algebraically, we could express this by solving , where t is the distance from one tick to the next. The variable m is located 8 tick marks past 1, so it will equal . We have uniquely determined the value of m, so Statement (1) is sufficient.

Statement (2) can be simplified as









Meanwhile, if we again consider t to be the value of a tick, then we can define and . Substituting those into the prior expression yields



We can stop right here, knowing that we can solve for t, since we have a linear equation with one variable. If we continued it would yield , , ,and . We have solved for the width of a tick mark, so we can determine the value of m as we did in Statement (1). Therefore, Statement (2) alone is sufficient.

The correct answer is (D).