Final answer:
By adding Monday's earnings and subtracting Tuesday's losses from Mark's initial investment, we find that the value of his investment account after Tuesday is $5,260.67.
Step-by-step explanation:
Mark's investment account initially has $5,272.56. On Monday, the account earned $26.74, and on Tuesday, the account lost $38.63. To calculate the value of Mark's investment account after Tuesday, we need to add the earnings from Monday and then subtract the loss from Tuesday.
Starting with $5,272.56, after Monday's earning, the new total is $5,272.56 + $26.74 = $5,299.30. Then, after Tuesday's loss, the new total is $5,299.30 - $38.63 = $5,260.67. Hence, the value of Mark's investment account after Tuesday is $5,260.67, which corresponds to answer choice A. $5,260.67.