#### Answer

(a) $QR = 6.4$
(b) $MP = 10.6$

#### Work Step by Step

(a) The diagonals of a parallelogram bisect each other. Therefore the point R is the midpoint of $\overline{QN}$
We can find $QR$:
$QR = \frac{QN}{2} = \frac{12.8}{2} = 6.4$
(b) The diagonals of a parallelogram bisect each other. Therefore the point R is the midpoint of $\overline{MP}$
We can find $MP$:
$MP = 2\times MR = (2)(5.3) = 10.6$