For variable capacitor, a simple MOS cap can do it. Simply change the bias at gate, the overall capacitance will change according to the bias. Some other advance variable capacitor like accumulation mode is also good
In most cases variable resistor can be done by MOS working in triode region. Again, the resistance is determined by the votlage applied to the gate relative to the voltage at both source and drain. However, given the value you want, seems like it is kind of tough to get it.