Let

denote the particle's position. Then its velocity is given by


The speed is then given by the absolute value/magnitude/norm of the velocity function,
Part A: The answer is PR = 15.23 by Pythagorean Theorem.
The pythagorean theorem is a^2 + b^2 = c^2.
Plug in 14 for a and 6 for b to find c.
Part B: The answer is QR = 7.75.
Using the same theorem, plug 16 in for c, 14 in for a, and then you can find b.
A SCATTER PLOT IS JUST A DOT PLOT