Help me please, this has time

Which expression defines Sn?

Can someone answer it, and plot it, for 20 points and brainliest answer? p.s. they're the same ! : )

Calculate the density of benzene if 300ml of it weighs 263g. a. 0.88 g/ml b. 1.14 g/ml c. 78,900 g/ml d. 37 g/ml

What is the area of the triangle 10 13 12