A biochemist is testing the effect of a new antibiotic on a particular mould growing in a petri dish. Without the antibiotic the mould grows as a circular patch with the radius increasing with time according to r = 0.5t cm where t is measured in hours since the mould was introduced to the petri dish. The area of the mould is given by A = ², the area of a disc of radius r. When the radius of the disc reaches 2cm the biochemist introduces the antibiotic. This causes the radius of the disc to reduce according to r = 2 - √tcm where t is measured in hours since the antibiotic was introduced. (a) What was the time duration of the entire experiment (from the introduc- tion of the mould until its disappearance)? (b) Graph the radius of the disc against elapsed time since the start of the experiment. (c) How fast was the area of the disc increasing (cm²/hour) just before the antibiotic was introduced?

A biochemist is testing the effect of a new antibiotic on a particular mould growing in a petri dish. Without the antibiotic the mould grows as a circular patch with the radius increasing with time according to r = 0.5t cm where t is measured in hours since the mould was introduced to the petri dish. The area of the mould is given by A = ², the area of a disc of radius r. When the radius of the disc reaches 2cm the biochemist introduces the antibiotic. This causes the radius of the disc to reduce according to r = 2 - √tcm where t is measured in hours since the antibiotic was introduced. (a) What was the time duration of the entire experiment (from the introduc- tion of the mould until its disappearance)? (b) Graph the radius of the disc against elapsed time since the start of the experiment. (c) How fast was the area of the disc increasing (cm²/hour) just before the antibiotic was introduced?

Elementary Geometry For College Students, 7e

7th Edition

ISBN:9781337614085

Author:Alexander, Daniel C.; Koeberlein, Geralyn M.

Publisher:Alexander, Daniel C.; Koeberlein, Geralyn M.

Chapter9: Surfaces And Solids

Section9.3: Cylinders And Cones

Problem 14E: A cylindrical orange juice container has metal bases of radius length 1 in. and a cardboard lateral...

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