Describe the shape of the graph

Ijust need to see how to do this. so you don’t have to answer all of them just a step by step explanation of one.

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

David leaves his house to go to school. he walks 200 meters west and 300 meters north. how far is david from his original starting point?