A liquid state detecting sensor is provided in which a level detecting unit for detecting the level of a liquid and a concentration detecting unit for detecting the concentration of a particular component contained in the liquid are integrated. The low noise amplifier module may include a first switching circuit coupled to the antenna, a second switching circuit coupled to the transceiver, at least one low noise amplifier coupled between the first and second switching circuits, and a transmit bypass path coupled between the first and second switching circuits. The lock is rotated so that the entrance to the slot is blocked and the post cannot slide out of the slot. The polymerization initiator contains two types of organic peroxides that do not produce oxygen gas resulting from the decomposition thereof and have different one-minute half-life temperatures.