Examples of properties communative, associative, and identity?

Colby and jaquan are growing bacteria in an experiment in a laboratory. colby starts with 50 bacteria in his culture and the number of bacteria doubles every 2 hours. jaquan starts with 80 of a different type of bacteria that doubles every 3 hours. let x equal number of days. colbys experiment follows the model: a.) y=50*2^x b.) y=50*2^8x c.) y=50*2^12x jaquans experiment follows the model: a.)80*2^x b.)80*2^8x c.)80*2^12x

If f(x) = x+8 and g(x) = 4x- 3, find (f+g)(x)

Cody was 165cm tall on the first day of school this year, which was 10% taller than he was on the first day of school last year.