Pea aphids, Acyrthosiphon pisum, are small, wingless, sap-sucking insects that live on plants. They evade predators (such as ladybugs) by dropping off the plants. A study examined the mechanism of aphid drops. Researchers placed aphids on a leaf positioned at four different heights (in centimeters, cm) above a surface covered with petroleum jelly. When a ladybug was introduced, the aphids dropped and the petroleum jelly helped capture their landing posture (upright or not). Each aphid performed this experiment only once. The table contains the findings.
Dropping Height Landing Posture
3 cm Upright 20 Not upright 10 Sample Size 30
5 cm Upright 23 Not upright 30 Sample Size 30
10 cm Upright 27 Not upright 30 Sample Size 30
20 cm Upright 29 Not upright 30 Sample Size 30
(a) Using the plus four method, give four 95% confidence intervals for the percents of aphids that land upright when dropping from 3, 5, 10, and 20 cm: (Enter your answers rounded to three decimal places)