Question

27 A square field measures 10 meters by 10 meters. Ten students each mark off a randomly selected region of the field; each region is square and has side lengths of 1 meter, and no two regions overlap. The students count the earthworms contained in the soil to a depth of 5 centimeters beneath the ground's surface in each region. The results are shown in the table below. 25 Region h = - 4.9t2 + 25t The equation above expresses the approximate height h, in meters, of a ball t seconds after it is launched vertically upward from the ground with an initial velocity of 25 meters per second. After approximately how many seconds will the ball hit the ground? A B с D E Number of Number of earthworms Region earthworms 107 F 141 147 G 150 146 H 154 135 I 176 149 J 166 A) 3.5 B) 4.0 C) 4.5 D) 5.0 Which of the following is a reasonable approximation of the number of earthworms to a depth of 5 centimeters beneath the ground's surface in the entire field? A) 150 B) 1,500 C) 15,000 D) 150,000

Answer 1

25) ha -4.94 + 25+ To hit ground, h=o -4.94 + 25 tao tl -4.94 + 25) =0 -4.95 + 25 20 tco t = - 25 -4.9 t = 5.102 t z 5 seconds option o