19. What is the most likely outcome of increasing the number of slits per unit distance on a diffraction grating? a. lines become narrower b. distance between lines increases c. lines become thicker d. distance between lines decreases

it doesn't. it was imagined up in the middle ages.

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