SCHOOL LUNCH In 2015, Ed spent $800 buying lunches. In 2017, he spent $300 buying lunches. What was the rate of change from 2015 to 2017? Plz help asap plz

Consider a graph for the equation y= -3x+4. what is the y intercept? a) 4 b) -4 c) 3 d) -3

Factor k2 - 17k + 16. a.(k - 2)(k - 8) b.(k - 1)(k + 16) c.(k - 1)(k - 16)

Ariana starts with 100 milligrams of a radioactive substance. the amount of the substance decreases by 20% each week for a number of weeks, w. the expression 100(1−0.2)w finds the amount of radioactive substance remaining after w weeks. which statement about this expression is true? a) it is the difference between the initial amount and the percent decrease. b) it is the difference between the initial amount and the decay factor after w weeks. c) it is the initial amount raised to the decay factor after w weeks. d) it is the product of the initial amount and the decay factor after w weeks.