Please help ! thank you :)

Super ultra mega important if you can answer this correctly i will give you 100 points but if you don't answer it correctly you'll get a big report. so stay aware and have a nice day!

An arc subtends a central angle measuring 7pi/4 radians what fraction of the circumference is this arc?

Rewrite the following quadratic functions in intercept or factored form. show your work. y = 5x^2 + 10x