There Are Exactly Two Cars in the Lot

question 15

Multiple Choice

There are exactly two cars in the lot.

• A) (∃x)(∃y){Cx • Lx • Cy • Ly • x ≠ y • (z)[(Cz • Lz) ⊃ (z = x ∨ z = y)}
• B) (∃x)(∃y)(Cx • Lx • Cy • Ly • x ≠ y)
• C) (x)(∃y){Cx • Lx • Cy • Ly • x ≠ y • (z)[(Cz • Lz) ⊃ (z = x ∨ z = y)}
• D) (∃x)(∃y)(∃z){Cx • Lx • Cy • Ly • x ≠ y • [(Cz • Lz) ⊃ (z = x ∨ z = y)}
• E) (x)(y){[Cx • Lx • Cy • Ly • x ≠ y] ⊃ (z)[(Cz • Lz) ⊃ (z = x ∨ z = y)}

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Definitions:

PB2

PB2 often refers to a secondary or specific pushbutton in a system, indicating its role or position within a sequence of controls.

Retentive On-Delay

A timing function in control systems that starts counting upon receiving an input signal and retains its timing value across power cycles, activating its output after a set delay.

Retentive Timer

A type of PLC timer that retains its value even after the power is turned off or the controlling logic is no longer true.