Four ingredients costing $320 per kg, $240 per kg, $160 per kg and $80 per kg are mixed so that their masses are in the ratio 4:1:3:2. Calculate the average cost per kg of the mixture.

Nick estimated that 5/8+4/7 is about 2.explain how you know his estimate is not reasonable plz and fast i will give 50 points

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 california was approximately two times the population of florida. b. the population of florida was approximately twenty times the population of california. c. the population of florida was approximately two times the population of california. d. the population of california was approximately twenty times the population of florida.

If t8 = 4 and t12 = −2, find the first three terms of the arithmetic sequence.