What do plasmids often contain that is helpful for bacterial survival

there are 35 white marbles

step-by-step explanation:

y- yellow marbles

4y + 5 = 45

subtract 5 from both sides

4y = 40

divide for from both sides

y = 10

plug in 10 to get 40 yellow marbles then subtract by 5 to get 35 marbles

thus there are only 10 yellow marbles

not sure if this what   you'r looking for would be percent composition

not too sure but maybe in the hot springs.