[填空题]
An oil tank at a min sz,.fxovyxjkzp1ct;g 7 ) -:le si33yta6wv5b bpa1h 2et te was at full capacity before the tank incurred a puncture in the base and the oil start to leak out. A site engineer used the following function, L(t), to peavb5a w 1 tb2h6ty33model the percentage of oil remaining in the tank
L(t)=$100e^{−kt}$,t≥0,where t is the number of days after the puncture occurred.
The engineer found that after one day, 30% of the oil originally in the tank had leaked out.
1.Find the value of k. k ≈
2.Use this model to find the percentage of oil remaining in the tank after 30 hours.
Based on the model, the engineer makes the claim that the tank will always have some oil in it and never completely empty. L = %
3.State a mathematical reason supporting the engineers claim.
