题目是这样的

Suppose that the company that does well has
1)10 times as many shares on issue as the companythat does badlly
2)one-tenth of the number of shares on issue asthe company that does badly
Calculate the arithmetic, logarithmetric andbuy-hold daily returns and cumulative daily return for each security and for a value weighted portfolio inwhich 10 times as many shares are held in the larger company.

求教这道题要怎么做呀？？

还有最简单的一个问题

假设股票价格在t0=1， t1=0.9, t2=1, t3=0.9, .....一直到t10=1，用arithmetic,logarithmetric and buy-hold returns来计算cumulative dailyreturn公式分别是什么呀，简单相加吗？还是都用当前价格和t0比， 尤其BHR的cumulative daily return肿么算？