Congress forcing a compromise(d) Space Shuttle design on NASA. Among other things, the space shuttle was the first human space vehicle to use solid rocket boosters. Solid rocket boosters were previously deemed unsafe for human space flight because once they're lit, they don't stop boosting until the fuel is gone. Liquid-fueled rockets can be shut off.
Definition of conductive. : having conductivity : relating to conduction (as of electricity)
Lower pH corresponds with higher [H + ], while higher pH is associated with lower [H + ]. Electrical conductivity (EC) is a measurement of the dissolved material in an aqueous solution, which relates to the ability of the material to conduct electrical current through it.