Crude oil imports to one country from another for 2009–2013 could be approximated by the following model where t is time in years since the start of 2000. I(t) = −33t2 + 800t − 3,000 thousand barrels per day (9 ≤ t ≤ 13) According to the model, approximately when were oil imports to the country greatest?

The oil imports to the country are greatest during the year 2012

Given the model where t is time in years since the start of 2000 expressed as I(t) = −33t² + 800t − 3,000

The oil imports more oil during the year 2012, is t = 12

I(12) = −33(12)² + 800(12) − 3,000

I(12) = -33(144) + 9600 - 3000

I(12) = -4752 + 6600

I(12) = 1848

Hence the oil imports to the country are greatest during the year 2012

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Import in 2012 was the greatest

Step-by-step explanation:

Given

l(t) = -33t² + 800t - 3000

9 ≤ t ≤ 13

Required

Determine the year with highest import.

To do this we simply substitute the values of t from 9 to 13 in the given function.

When t = 9

l(t) = -33t² + 800t - 3000

l(9) = -33 * 9² + 800 * 9 - 3000

l(9) = -33 * 81 + 800 * 9 - 3000

l(9) = -2673 + 7200 -3000

l(9) = 1527

When t = 10

l(10) = -33 * 10² + 800 * 10 - 3000

l(10) = -33 * 100 + 800 * 10 - 3000

l(10) = -3300 + 8000 - 3000

l(10) = 1700

When t = 11

l(11) = -33 * 11² + 800 * 11 - 3000

l(11) = -33 * 121 + 800 * 11 - 3000

l(11) = -3993 + 8800 - 3000

l(11) = 1807

When t = 12

l(12) = -33 * 12² + 800 * 12 - 3000

l(12) = -33 * 144 + 800 * 12 - 3000

l(12) = -4752 + 9600 - 3000

l(12) = 1848

When t = 13

l(13) = -33 * 13² + 800 * 13 - 3000

l(13) = -33 * 169 + 800 * 13 - 3000

l(13) = -5577 + 10400 - 3000

l(13) = 1823

Comparing the values of l(t) for the range of t = 9 to 13,

The highest value of l(t) is:

l(12) = 1848

Hence, the year with the highest import is 2012