$9.$ What is the result of improper balancing in a multi$-$cylinder engine's crankshaft?

$-$ A$)$ Decreased power output

$-$ B$)$ Increased oil consumption

$-$ C$)$ Premature bearing wear

$-$ D$)$ Reduced exhaust emissions

$10.$ How does the addition of a damper influence the critical speed of a rotating system?

$-$ A$)$ Increases the critical speed

$-$ B$)$ Decreases the critical speed

$-$ C$)$ Does not affect the critical speed

$-$ D$)$ Shifts the critical speed to a lower operational range