Solve Each Applied Problem $336 \mathrm{lb}$ And $125 \mathrm{lb}$ That Form an Angle Of

Solve each applied problem.
(a) Find the magnitude of the resultant of forces of $336 \mathrm{lb}$ and $125 \mathrm{lb}$ that form an angle of $27.3^{\circ}$ .
(b) A $712 \mathrm{ft}$ sidewalk connects the library and the physics lab. A $603 \mathrm{ft}$ sidewalk connects the library and the dining hall. If the angle between these sidewalks is $51.7^{\circ}$ , how long is the sidewalk connecting the physics lab and the dining hall?
(c) Find the horizontal and vertical components of a vector with magnitude 817 that is inclined $126^{\circ} 45^{\prime}$ from the horizontal. Give your answer in the form $|a, b|$ .
(d) A mother is standing 20 feet away from one of her children and 6 feet away from her other child. The angle between her lines of sight to her two children is $42.2^{\circ}$ . How far apart are the two children?