What are these i don't get it?

Since opening night, attendance at play a has increased steadily, while attendance at play b first rose and then fell. equations modeling the daily attendance y at each play are shown below, where x is the number of days since opening night. on what day(s) was the attendance the same at both plays? what was the attendance? play a: y = 8x + 191 play b: y = -x^2 + 26x + 126

The weights of broilers (commercially raised chickens) are approximately normally distributed with mean 1387 grams and standard deviation 161 grams. what is the probability that a randomly selected broiler weighs more than 1,425 grams?

What unit of been sure would be appropriate for the volume of a sphere with a radius of 2 meters