You are allowed to work a total of no more than 30 hours each week at your two jobs. Lawn mowing pays $5 per hour and babysitting pays $8 per hour. You need to earn at least $300 per week. You decide to write a system of inequalities to help determine the amount of time you can work at each job, where x represents the number of hours you mow lawns y represents the number of hours you babysit. You write the first inequality as x+y<30. Write the second inequality you would use for this system .

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.