PLEASE HELP ME WITH MATH

If f(x)=-x^2+6x-1 and g(x)=3x^2-4x-1,find(f+g)(x)

The number of fish in a lake can be modeled by the exponential regression equation y=14.08 x 2.08^x where x represents the year

Aculture started with 4,000 bacteria. after 5 hours, it grew to 5,200 bacteria. predict how many bacteria will be present after 19 hours. round your answer to the nearest whole number.