Notation question

[john f]

I'm having a (quiet) dispute about how to notate the rate of administration of a drug (but it would apply to many other situations, e.g. expressing acceleration):

For example, I consider administering a dose of a drug at '2 mg/kg/min' as old-fashioned, and believe a more logical expression would be: '2 mg / kg-min'

Or, the acceleration of a body expressed in the 'old' way would be: '9.8 m/sec/sec' wheras I think a better way would be '9.8 m / sec-sec' or '9.8 m / sec^2' or '9.8 m / sec * sec'

Any comments? Is there an 'official' site one could visit that describes 'best practices'?

Thank you!