Halley's Comet Returns to the Vicinity of the Sun (And $\times$

question 79

Multiple Choice

Halley's comet returns to the vicinity of the sun (and Earth) about once every 76 years.Its last appearance was in 1986.What is the average distance from Halley's comet to the sun,given that the average distance from Earth to the sun is 1.50 $\times$ 10¹¹m?

• A)6.4 \(\times\) 10¹¹ m
• B)1.8 \(\times\) 10¹² m
• C)2.7 \(\times\) 10¹² m
• D)1.1 \(\times\) 10¹³ m
• E)9.9 \(\times\) 10¹³ m

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Definitions:

Retentive

Memory or functions in a control system that retain their value or state even after the system is powered down or rebooted.

Nonretentive

In PLC programming, a term referring to memory or data that is not retained after power loss.

Retentive Timer Reset

A function in PLC programming that allows a timer to retain its accumulated value even after a reset condition has been removed or power to the PLC has been cycled.

Timer Resets

The process of returning a timer to its initial state or set value in control systems or programming.