The scientific phenomena that allows magnets to brake a roller coaster to a stop is O Lenz's Law
Snail's Law
O Newton's Law
O Faraday's Law

-4 on

see the picture for the vector

the magnitude of the vector by pythagorean theorem

r = √( (-10)^2 + (3)^2 ) = √109

magnitude = √109 units

the direction angle between vector and x-axis is

tan^(-1)(3/10) = 16.699

so the direction is approximately 16.7 degrees north of west

b. a lightning bug, plug of grass, and a worm