<Tr> <Td> kilogram </Td> <Td> kg </Td> <Td> mass </Td> <Td> "The kilogram is the unit of mass; it is equal to the mass of the international prototype of the kilogram ." 3rd CGPM (1901, CR, 70) </Td> <Td> The mass of one litre of water at the temperature of melting ice . A litre is one thousandth of a cubic metre . </Td> <Td> </Td> </Tr> <Tr> <Td> second </Td> <Td> s </Td> <Td> time </Td> <Td> "The second is the duration of 7009919263177000000 ♠ 9192631770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium 133 atom ." 13th CGPM (1967 / 68, Resolution 1; CR, 103) "This definition refers to a caesium atom at rest at a temperature of 0 K ." (Added by CIPM in 1997) </Td> <Td> The day is divided in 24 hours, each hour divided in 60 minutes, each minute divided in 60 seconds . A second is 1 / (24 × 60 × 60) of the day . </Td> <Td> </Td> </Tr> <Tr> <Td> ampere </Td> <Td> </Td> <Td> electric current </Td> <Td> "The ampere is that constant current which, if maintained in two straight parallel conductors of infinite length, of negligible circular cross-section, and placed 1 metre apart in vacuum, would produce between these conductors a force equal to 6993200000000000000 ♠ 2 × 10 newton per metre of length ." 9th CGPM (1948) </Td> <Td> The original "International Ampere" was defined electrochemically as the current required to deposit 1.118 milligrams of silver per second from a solution of silver nitrate . Compared to the SI ampere, the difference is 0.015% . </Td> <Td> </Td> </Tr> <Tr> <Td> kelvin </Td> <Td> </Td> <Td> thermodynamic temperature </Td> <Td> "The kelvin, unit of thermodynamic temperature, is the fraction 1 / 7002273160000000000 ♠ 273.16 of the thermodynamic temperature of the triple point of water ." 13th CGPM (1967 / 68, Resolution 4; CR, 104) "This definition refers to water having the isotopic composition defined exactly by the following amount of substance ratios: 0.000 155 76 mole of H per mole of H, 0.000 379 9 mole of O per mole of O, and 0.002 005 2 mole of O per mole of O ." (Added by CIPM in 2005) </Td> <Td> The Celsius scale: the Kelvin scale uses the degree Celsius for its unit increment, but is a thermodynamic scale (0 K is absolute zero). </Td> <Td> Θ </Td> </Tr>

Which of the following units are not si units