During a ten day period kids were given $1 on the first day $2 on the second day, and so on finishing with $10 on the 10th day. how much did the children receive during the 10 day period? i need to show the work but in another way than addition

When you answer this can you explain

Martha has a deck of cards. she has lost some of the cards, and now the deck only contains nine spades, eleven diamonds, eight clubs, and twelve hearts. martha predicts that whenever she draws a card from the deck without looking, she will draw a club one-fifth of the time. which activity would best allow martha to test her prediction? a. randomly draw a card from the box and see if it is a club. b. randomly draw a card. then, continue to draw another card until all eight clubs are drawn. c. randomly draw and replace a card 120 times. then, observe how close to 30 times a club is drawn. d. randomly draw and replace a card 100 times. then, observe how close to 20 times a club is drawn.

Ellen makes and sells bookmarks. she graphs the number of bookmarks sold compared to the total money earned. why is the rate of change for the function graphed to the left?