2. Sam is collecting pennies. On the first day of the month, Sam is given 10 pennies. Each day after than he gets 2 more pennies. Which of the following equations defines how many pennies he has after the
nth day?
an = 10n + 2
an = 10n - 2
an = 20n - 20
an = 2n + 10

Jeffery conducted a survey in his school and found that 30 of the 50 eighth grade students' favorite subject is mathematics. based on the results, jeffery concluded that out of the 200 students in his school, 120 students' favorite subject is mathematics. select the statement that is true about jeffery's conclusion. a. jeffery's conclusion is not valid because the sample was biased since only 200 students were surveyed. b. jeffery's conclusion is valid because the sample was random since all of the students were eighth grade students. c. jeffery's conclusion is valid because the sample was random. d. jeffery's conclusion is not valid because the sample was biased since all of the students were eighth grade students.

According to the 2008 u.s. census, california had a population of approximately 4 × 10^7 people and florida had a population of approximately 2 × 10^7 people. which of the following is true? a. the population of florida was approximately two times the population of california. b. the population of florida was approximately twenty times the population of california. c. the population of california was approximately twenty times the population of florida. d. the population of california was approximately two times the population of florida.

The diagonals of a quadrilaretral intersect at (-1,4). one of the sides of the quadrilateral is bounded by (2,7) and (-3,5) determine the coordinates of the other side in order for the quadrilaretral to be a square.