The pH scale measures how acidic or basic a substance is. Normal drinking water needs to have a pH of less than 8.5 and greater than 6.5. Model the normal range of pH values of water, using a compound inequality. Thank you! A. 6.5 < x < 8.5
B. 6.5 > x > 8.5
C. 6.5 ≤ x ≤ 8.5
D. 6.5 ≥ x ≥ 8.5

Consider the following geometry problems in 3-space enter t or f depending on whether the statement is true or false. (you must enter t or f -- true and false will not work.) f equation editorequation editor 1. a plane and a line either intersect or are parallel t equation editorequation editor 2. two planes parallel to a third plane are parallel f equation editorequation editor 3. two lines either intersect or are parallel f equation editorequation editor 4. two planes orthogonal to a third plane are parallel f equation editorequation editor 5. two planes orthogonal to a line are parallel f equation editorequation editor 6. two planes either intersect or are parallel f equation editorequation editor 7. two lines orthogonal to a third line are parallel t equation editorequation editor 8. two lines parallel to a third line are parallel t equation editorequation editor 9. two planes parallel to a line are parallel f equation editorequation editor 10. two lines parallel to a plane are parallel f equation editorequation editor 11. two lines orthogonal to a plane are parallel