Imagine that you design running shoes for a living. Which biometric would be most useful? A.
the average weight of a runner
B.
the number of runners in a popular urban area
C.
the points of impact when the foot hits the ground
D.
the distance that beginning runners attempt to finish

The vector a? is 3.50 cm long and is directed into this page. vector b? points from the lower-right corner of this page to the upper-left corner of this page and has the components bx=-19.5 cm , by=25 cm. in the right-handed coordinate system, where the +x-axis directed to the right, the +y-axis toward the top of the page, and +z-axis out of the page, find the x-component of the vector product a? ×b? , measured in cm2.