A student performs a ballistic pendulum experiment using an apparatus similar to that shown in the first figure. She obtains the following average data: h = 8.64 cm, projectile mass m 70.0 g, and pendulum mass m = 263 g. (a) Determine the initial speed V1A of the projectile. m/s (b) The second part of her experiment is to obtain VA by firing the same projectile horizontally (with the pendulum removed from the path) and measuring its horizontal position x and distance of fall y, as shown in the second figure. What numerical value does she obtain for V1A on the basis of her measured values of x = 250 cm and y = 83.2 cm? m/s (c) What factors might account for the difference in this value compared to that obtained in part (a)?