Look at the pictures below. Which of these pictures shows physical weathering processes by which soil is formed?
Picture 1 and Picture 3
Picture 2 and Picture 4
Picture 2 and Picture 3
Picture 3 and Picture 4

Astudent poured a solution of bromothymol blue indicator into three test tubes. then he placed an aquatic plant in two of the test tubes, as shown below. he placed a stopper on each test tube and placed them all in the dark for 24 hours. bromothymol blue turns from blue to yellow in the presence of co2