We can use the formula for compound interest to solve this problem: A = P * (1 + r/n)^(n*t), where A is the final amount, P is the principal amount, r is the annual interest rate, n is the number of times interest is compounded per year, and t is the time in years.
In this case, we have:
A = $28,000
r = 2% = 0.02
n = 365 (since interest is compounded daily)
t = 6
We want to solve for P. Substituting the given values into the formula, we get:
$28,000 = P * (1 + 0.02/365)^(365*6)
Dividing both sides by (1 + 0.02/365)^(365*6), we get:
P = $28,000 / (1 + 0.02/365)^(365*6) = $22,406.57
Therefore, Marques would need to invest $22,407 (rounded to the nearest dollar) for the value of the account to reach $28,000 in 6 years.