Pleaseee help, I’ve been trying for hours

Taking algebra two apex courses and need with these questions

You receive 15% of the profit from a car wash how much money do you receive from a profit of 300

A33 gram sample of a substance that's used to detect explosives has a k-value of 0.1473. n = noekt no = initial mass (at time t = 0) n = mass at time t k = a positive constant that depends on the substance itself and on the units used to measure time t = time, in days