Please give me the right answer to this and I'll give you BRANIEST if you get it right. No links ​

All per-unit concepts rely on ratios,meaning,to provide a type of measurement

Find the magnitude, correct to two decimal places, made by each of the following with positive direction of the x axis a) y= x the answer is 45° but i don’t know how

Kevin's bank offered him a 4.5% interest rate for his mortgage. if he purchases 3 points, what will be his new rate?