Self-study
Chelas and Stelma are required to leave their respective stations immediately to pursue any prisoner who attempts to escape from their sector. ████████████ ██████ ████ ███ ████████ ████ █ █████████ ██████ ███ ██████ ███ █████████ ██ █████ █████ ████████ █████ █████ ████████████ ████ ████████ ██ ███ ██ ██ █ █████ ████ ██████ ███ ██████ ████████ ███ █████████ █████ ██ █████ ██████ ███ █████ ████████████ ████████ ██ ███ ██████████ ████ ██████ ███ ████████ █████ █████ ███ ██████ ███ ████
Summary
For both C and S, if a prisoner tries to escape from their sector, C and S must leave their respective stations to pursue the prisoner.
If they are not pursuing an escaped prisoner, C and S cannot leave their stations until their replacements have arrived.
On May 11 at 9pm, C and S finished a four-hour shift and their replacements arrived at the end.
C had violated the rules described. S had not violated the rules described.
Notable Valid Inferences
There’s no clear inference to draw, because there are many ways in which C could have violated the rules and S would not violate the rules. Let’s use process of elimination to identify what must be false.
18.
If the statements above are █████ ████ ██ ███ █████████ █████ ██ ████ ███████
a
Chelas and Stelma ████ ██ █████ ██████████ ████████ ██ █ ████
Could be true. C could have violated the rules by leaving his station and coming back before the end of the shift. Or C could have violated by failing to pursue a prisoner. S could have stayed at her station the whole time. Or she could have pursued an escaped prisoner.
b
Stelma left her ███████ ██████ █ ████ ███ ██████ ███ ████
Could be true. S could have left to pursue an escaped prisoner. And C could have violated by failing to pursue that escaped prisoner.
c
Chelas left his ███████ ██████ █ ████ ███ ██████ ███ ████
Could be true. C could have violated by leaving the station even though a prisoner wasn’t trying to escape. S could have followed the rules and stayed at her station.
d
A prisoner attempted ██ ██████ ████ ██████ ███ ████████ ██████ ██ █ ████ ███ ███████ ██████ ███ ██████ ████ ███ ██ ███ ███████ ██████ █ ████
Must be false. If a prisoner tried to escape from the sector at 7pm, S had to leave her station to pursue the prisoner, because we know she followed the rules.
e
A prisoner attempted ██ ██████ ████ ██████ ███ ████████ ██████ ██ █ ████ ███ ████ ██████ ███ ██████ ████ █████ ████████ ██████ █ ████
Could be true. S could have followed the rules by chasing the escaped prisoner. C could have violated the rules by leaving the station but for some other reason besides chasing the prisoner.