Productivity and Yield of Cultivated Crops Are Often Reduced by Insect

question 128

Essay

Productivity and yield of cultivated crops are often reduced by insect pests.The following graph shows the relationship between the yield of a certain crop, , as a function of the density of aphids x.(Aphids are small insects that suck plant juices.) Here, is measured in kilograms/ 4,000 square meters, and x is measured in hundreds of aphids/bean stem.By computing the slopes of the respective tangent lines, estimate the rate of change of the crop yield with respect to the density of aphids when that density is 200 aphids/bean stem and when it is 800 aphids/bean stem.

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Definitions:

Braxton-Hicks Contractions

Irregular, usually painless uterine contractions that occur throughout pregnancy, often mistaken for labor pains.

Cervix

The narrow lower end of the uterus, through which a baby passes to reach the vagina.

Pregnancy

The condition or period of being pregnant, involving the development of one or more offspring inside a woman's uterus.

Small-For-Gestational-Age

Refers to babies who are born weighing less than the norm for their gestational age.