Colleen is knitting a scarf. For every 45 pieces of blue yarn she uses, she uses 18 pieces of red yard. What equation can be used to represent the proportional relationship between the amount of blue yarn, b, and red yard, r, that Colleen uses when knitting a scarf?

"curse these trig-loving pirates! " devora mutters as she looks at the map. then, after thinking for a moment, she walks back to the entrance of the secret cave, measuring 48 meters along the way. after performing a calculation, devora walks back to the empty treasure, faces the entrance, and turns a certain number of degrees to her left before walking 89 meters to the treasure. supposing that the angle at the cave entrance is acute and that devora's calculations were correct, how many degrees did she turn?