Q/ Four point charges Q. 2Q, -Q. -20 are located at (0,0.a). (0,0.2a). (0.0,-a). and (0,0-2a) respectively. Derive an expression for the potential and the electric field intensity E at the point (x, y,z). Hint: assume what you think is suitable.​

You’re ordering more thread for blue jeans co. you usually purchase from ted’s threads, which sells 12 thread spools for $27. you recently received a notice from wade's wares that says you can buy thread from them for $2.30 each for the first 2 dozen and $2 a spool thereafter. you need to order 5 dozen spools. what percentage can you save by going with wade’s wares?