Could someone PLEASE help me with these physics questions? These should be fairly easy

(3) A huge (essentially infinite) horizontal nonconducting sheet 10.0 cm thick has charge uniformly spread over both faces. The upper face carries 95 nC/m2 while the lower face carries -25 nC/m. What is the magnitude of the electric field at a point within the sheet 2.00 cm below the upper face?(4) 1') A small circular loop of wire with radius r = 1 cm is placed at the center of a large circular loop of wire with radius R = 100m. The two 100ps lie in the same plane, and 9"