Over a four$-$year period, LaKeisha Thompson purchased shares in the Oakmark Investor Class Fund. Using dollar cost averaging, calculate the number of shares before completing this problem. $($Round your answers to the nearest whole number.$)[[$Year$,$Investment Amount,Price per Share,Number of Shares$],[$February $2017,,1,300,,54\mathrm{.}00,],[$February $2018,,1,300,,35\mathrm{.}00,],[$February $2019,,1,300,,48\mathrm{.}40,],[$February $2020,,1,300,,56\mathrm{.}00,]]$ a$.$ At the end of four years, what is the total amount invested? Total investment b$.$ At the end of four years,

what is the total number of shares purchased?