What is 7 more than five times the number 9 divided by 15? ?

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 x is 6, then 7x= a. 13 b. 42 c. 42x d. 76

The area of a circle is equal to 1 dm². find the radius of the circle.