|one of the more modern hard case slider scientific models, but
before formula entry became usual. dual power, the machine has no off
button, but powers down after a short time.
a standard set of casio scientific function with fractions, delete key
and linear regression. unfortunately the segmented display has only 8
digits which is a shame, especially for fractions in which 355/226 cant be
trig functions work above 1440 degrees, unlike earlier