In a class of 20 students,12 were girls and the rest were boys A)What fraction of the class was boys?
B)What fraction of the class was girls?
C)What percent of the class was girls?
D)What decimal fraction of the class was boys

You are making a battery for a science project. you have copper wire for your first electrode. you need to choose a conductor, a second electrode, and a device to plug into your battery. you have already chosen a lemon conductor. complete each statement below about the options that include a lemon conductor.

Don't know how to find x given these segment lengths

Simplify. −4x^2 (5x^4−3x^2+x−2) −20x^6−12x^4+8x^3−8x^2 −20x^6+12x^4−4x^3+8x^2 −20x^8+12x^4−4x^2+8x −20x^6+12x^4+4x^3−8x^2