A certain bacteria starts with a population of 50. Every 3 hours, the population is halved. Write an algebraic function B(t) representing the population B(t) of a certain bacteria over time t, in hours.

For f(x)=2x+3 and g(x)=x^2- 8 find (f+g) (x)

Witch represents the inverse of the function f(x)=1/4x-12

The distribution of the amount of money spent by students for textbooks in a semester is approximately normal in shape with a mean of $235 and a standard deviation of $20. according to the standard deviation rule, how much did almost all (99.7%) of the students spend on textbooks in a semester?