To survey clients at a massage-therapy spa, a researcher alphabetically lists all of the customers the spa had last month. The researcher sends a survey to the 13th person on the list (with the number 13 being randomly chosen), then surveys every 20th customer after that. Which sampling method was used? A) cluster sampling
B) simple random sampling
C) stratified random sampling
D) systematic random sampling

Three friends went on a road trip from phoenix, az, to san diego, ca. mark drove 50 percent of the distance. jason drove 1/8 of the distance. andy drove the remainder of the distance. 1. andy thinks he drove 1/4 of the distance from phoenix, az, to san diego, ca. is andy correct? 2. the distance from phoenix, az, to san diego, ca, is 360 miles. how many miles did each person drive? 3. solve the problem. what is the answer in total?

White shapes and black shapes are used in a game. some of the shapes are circles. while the rest are squares. the ratio of the number of white shapes to the number of black shapes is 5: 11. the ratio of the number of white cicrles to the number of white squares is 3: 7. the ratio of the number of black circles to the number of black squres is 3: 8. work out what fraction of all the shapes are circles.

If you draw a card with a value of three or less from a standard deck of cards, i will pay you $43. if not, you pay me $11. (aces are considered the highest card in the deck.) step 1 of 2 : find the expected value of the proposition. round your answer to two decimal places. losses must be expressed as negative values.