Need help ASAP! I’m very confused!

Ivan began dividing g2  – 6 by g + 1, noting that . he started by placing g in the quotient, as shown below.what is g2  – 6 divided by g + 1? g –  1 –  g + 1  – g  –  7 + g  –  5  + 

How long must $542 be invested at a rate of 7% to earn $303.52 in interest? in a easier way

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.