Find derivative of f(x)= arctan(e^4x)

i know the formula is 1/ (1+x^2), x being the stuff inside tan, but i can't seem to do it right : (

Antonia and carla have an equivalant percentage of green marbles in their bags of marbles. antonia has 4 green marbles and 16 total matbles. if carla has 10 green marbles , how many total marbles does carla have

Points a, b, and c form a triangle. complete the statements to prove that the sum of the interior angles of triangle abc is 180

Find the area of a parallelogram with base 15 yards and height 21 2/3