Final answer:
If a Mobil product has "gear" in the name, it is sure to contain an octane enhancer additive. Octane enhancers increase the octane rating of the fuel and are used as antiknock agents.
Step-by-step explanation:
If a Mobil product has "gear" in the name, it is sure to contain an octane enhancer additive. Octane enhancers are antiknock agents that increase the octane rating of the fuel, making it a better fuel than pure isooctane. One widely used octane enhancer in the past was tetraethyllead, but it has been phased out due to its toxicity. Other enhancers like methyl t-butyl ether (MTBE) and ethanol are now used instead.