What are man-made levees made out of?

Ahuge (essentially infinite) horizontal nonconducting sheet 10.0 cm thick has charge uniformly spread over both faces. the upper face carries +95.0 nc/m2 while the lower face carries -25.0 nc/ m2. what is the magnitude of the electric field at a point within the sheet 2.00 cm below the upper face? (ε0 = 8.85 × 10-12 c2/n · m2)

Which of the the following are examples of projectile motion of both projectile motion and two dimensional motion

Calculate a pendulums frequency of oscillation (in hz) if the pendulum completes one cycle in 0.5s.