at the beginning of a trip the odometer on a car reads 30,680 and the car has a full tank of gas. At the end of the trip the odometer reads 30,970. it takes 20 gallons of gas to refill the tank. What is the average rate of the change of the number of miles with respect of the number of gallons

If 3x+8=3x+8 is it one solution or no solution

The distance of a chord from the centre of a circle is 12cm and the lenght of the chord is 10cm. find the radius of the circle

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.