A ball is thrown from an initial height of 4 feet with an initial upward velocity of 23 f/s. The ball's height h (in feet) after t seconds is given by the following. Find all values of t for which the ball's height is 12 feet.

Time taken = 0.85 and 0.59 (Approx.)

Step-by-step explanation:

Given:

Initial height = 4 feet

Initial upward velocity = 23 f/s

Equation;

h = 4 + 23t - 16t² for h = 12 feet

Find:

Time taken

Computation:

h = 4 + 23t - 16t² for h = 12 feet

12 = 4 + 23t - 16t²

16t² -23t + 8 = 0

t = [-b±√b²-4ac] / 2a

t = [23±√23²-(4)(16)(8)] / 2(16)

t = [23±√529-512] / 32

t = [23±4.12]/32

Time taken = 0.85 and 0.59 (Approx.)

15%

step-by-step explanation:

use the table and count the number of guesses that has two correct answers.

the following are two correct answers

10010, 01100, 11000

a total of 3 numbers having 2 correct guesses out of 20 questions.

probability of getting 2 correct guesses = the number of questions getting 2 correct answers / total number of questions.

= 3/20

to convert it into percent multiply by 100, we get

= 3/20 * 100

= 15%

the answer is 15%

you.