The great plain is sometimes called a breadbasket. why is that a appropriate name?

how is this physics related?

The great plains are called the breadbasket because they are the main producers of the US's wheat grain.

If your talking about Ukraine, the same reason applies but the food goes to russia

can be answered using momentum.

momentum = p

p1= mass1 * velocity1

p1 = p2

therefore

p1 = 6kg * 4m/s

p1 = 24kgm/s

p2=m2 * v2

24 kgm/s = 7kg * v2

v2 = 24 kgm/s / 7kg

v2= 3.42 m/s

c) up is the direction the magnetic force is acting on the charge.