Question 1150074
{{{ R(t) = -20t + 2020 }}}
( {{{ t }}} = yrs from now, {{{ R(t) }}}
in billions of barrels )
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(a)
{{{ R(6) = -20*6 + 2020 }}}
{{{ R(6) = -120 + 2020 }}}
{{{ R(6) = 1900 }}} billion barrels
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(b)
{{{ R(t) = 0 }}}
{{{ 0 = -20t + 2020 }}}
{{{ 20t  = 2020 }}}
{{{ t = 101 }}} yrs