Someone please help me pleaseee

Step-by-step explanation:

20: is a drawing with compasses and rular

18e³f+45e²f^4 ( take 9 as a common factor, e² and f)

9e²f(2e+5f^3)

x²-4x-12 ( factorize)

(x-6)(x+2)=0

either : x-6=0

then x=6

or x+2=0

then x=2

b) 1/3 * 1/5

step-by-step explanation:

each smallest part is 1/15 since the written one is 1/5 and it's divided by 3 equal parts. (1/5 )/3 = 1/15 = 1/3 * 1/5

step-by-step explanation:

infinity is the answer