I need HELP I cant figure this out​

Find an equation for the linear function which has slope -10 and x-intercept -7

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

If p(a) = 0.70 and p(b) = 0.20, then a and b are independent events if