a$.$ Refer to Figure $17\mathrm{.}1$ and locate the E$-$Mini contract on the Standard & Poor$$s $500$ Index. If the margin requirement is $12\%$ of the futures price times the multiplier of $$50,$ how much must you deposit with your broker to buy one December contract? $($Do not round intermediate calculations.$)$

b$.$ If the December futures price increases to $3,102,$ what percentage return will you earn on your investment? $($Do not round intermediate calculations. Round your answer to $2$ decimal places.$)$

c$.$ If the December futures price falls by $1\mathrm{.}1\%,$ what is the percentage gain or loss on your investment? $($Input the amount as positive value. Do not round intermediate calculations. Round your answer to $2$ decimal places.$)$