Apenny falls from a windowsill which is 25.0 m above the sidewalk. how much time does a passerby on the sidewalk below have to move out of the way before the penny hits the ground?

Charge is distributed along the entire x-axis with uniform density λ. how much work does the electric field of this charge distribution do on an electron that moves along the y-axis from y = a to y = b? (use the following as necessary: a, b, ε0, λ, and q for the charge on an electron.)