(2√5 + 3(√7))^2
(2√5 + 3(√7))(2√5 + 3(√7))
4*5 + 6√35 + 6√35 + 9*7
20 + 12√35 + 63
20 + 63 + 12√35
83 + 12√35
B would be the answer. hope it helps !
68.8% is your answer
when changing a decimal to a percentage, move the decimal point twice over
hope this helps
33.3 because 27/50=36/x and x=66.67 and thats how much as decayed after 36 hours but you want what is left so subtract from 100 and get 33.3