Self-study
Traffic engineers have increased the capacity of the Krakkenbak Bridge to handle rush-hour traffic flow. ███ █████████ ████████ ██ █████████ ███████ ████ █████ ███ ████ ████████ ███ ███ ████ ███ ████████ ██ ████████ ████████ ██████████ ████ ████ ██ ███ ███████ ██ ███ ██████ ██████ ███ ███ ██████ █████████ ███████████ █████ ███ ████ ████ ████████ ██ ███ ███████ ████ ██████ ███ ██████ ██████ ████ ████ ███ ███ ████ ██████████
Summary
Increasing the capacity of Krakkenbak Bridge caused an increase in rush-hour traffic flow.
If the city hadn’t invested in computer modeling technology last year, this traffic flow wouldn’t have increased.
If this traffic flow hadn’t increased, the city’s financial predicament wouldn’t have been resolved.
Very Strongly Supported Conclusions
If the city hadn’t invested in computer modeling technology, then the financial predicament wouldn’t have been resolved.
Since the financial predicament was resolved, this means that rush-hour traffic flow did increase and the city did invest in computer modeling technology.
18.
Which one of the following ███ ██ ████████ ████████ ████ ███ ███████████ ██████
a
The city's financial ███████████ █████ ███ ████ ████ ████████ ███ ███ ████ ██████ █ █████████ ████████ ████████ ████████ ████████
Unsupported. If the city hadn’t invested in computer modeling technology, then the financial predicament wouldn’t have been resolved. But the stimulus doesn't say anything about which software the company needed to choose; a competing software might have worked just as well.
b
The city's financial ███████████ █████ ███ ████ ████ ████████ ███ ███ ████ ███ ████████ ██ ████████ ████████ ███████████
Very strongly supported. By chaining the conditional claims, we see that if the city hadn’t invested in computer modeling technology, then rush-hour traffic flow wouldn’t have increased, and the financial predicament wouldn’t have been resolved.
c
On an average ████ ████ ███████ ███████ ███ ██████████ ██████ ████ ████ ██ ████████ ██ ████ █████
Unsupported. Just because rush-hour traffic flow increased doesn’t mean that overall traffic increased. There could be the same amount of traffic crossing the bridge this year, just more traffic flow at rush-hour.
d
Traffic flow across ███ ██████████ ██████ ██████ ████ ████ █████ ███ ████ █████████ ███ ███ ██████ █████ ███ ████ █████████ ██ ████████ ████████ ██████████ ███ ███████ █████████ ████████ ████ █████
Unsupported. Rush-hour traffic flow wouldn’t have increased if the city hadn’t invested in computer modeling technology. But just because the city invested in this technology doesn’t mean that it was their highest budgetary priority last year.
e
The city's mayor ███ █ █████████ ██ █████████ ██ ████████ ████████ ██████████ ███████ ██ ███ ██████ ████ ██ ████████ ███████ ████ ██████ ███ ██████████ ██████ ██████ ████ █████
Unsupported. We don’t know why the mayor supported investing in computer modeling technology. It did increase rush-hour traffic flow, but the mayor might’ve had other reasons for supporting it.