In 1983 the composition of pennies in the united states was changed due, in part, to the rising cost of copper. pennies minted after 1983 weigh 2.50 grams while the earlier copper pennies weigh 3.11 grams. a. a roll of pennies contains 50 pennies. if a particular roll of pennies weighs 138.42 grams, how many of the earlier copper pennies and how many of the after 1983 pennies does this roll contain? b. suppose you measure a roll of pennies on a scale which only reads the weight to the nearest gram. the scale says that the roll of pennies weighs 131 grams. what can you conclude about the pennies in this roll? what if the roll weights 134 grams? explain.

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