(1 + c)/(r + e + c). The money multiplier (also called the credit multiplier or the deposit multiplier) is a measure of the extent to which the creation of money in the banking system causes the growth in the money supply to exceed growth in the monetary base.
A buzzing light switch could mean the fixture is wearing out, causing an arc of electricity behind the wall plate. If this is the case, the potential for an electrical fire may exist.
In the bathroom, the bulb flickers on and off when it's switched off. Same when it was a CFL bulb before I switched to LED cause I hate CFLs. Our mains voltage is 220v. The bulb we have looks like this. If I remember correctly, I should add a capacitor in series to the bulb to fix this.