<PRE><B>Question 831450</B>
Express cm in terms of km
( 2 cm ) x ( 1m / 100 cm ) x ( 1 km / 1000 m )
{{{ 2*(1/100)*(1/1000) = 2/100000 }}}
{{{ 2/100000 = .00002 }}}
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( km ) / ( km/yr) = yrs
{{{ 36000 / .00002 = 1800000000 }}}
The rift started to open 1,800,000,000 yrs ago
This is 1 billion 800 million yrs ago

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