A heating coil operates on 220 V if it draws 15.0 A. Find it's resistance

a.   mass number from atomic number

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

answer( sicar );