Thank you for your question! You can do this computation using either a time value of money calculator to find the future value or the formula
FV = PMT * (((1 + rate)^n – 1) / rate)
Plugging in the values that we know here of PMT = $40, rate = 0.06/12 = 0.005, and n = 12*40 = 480, that becomes
FV = 40 * (((1 + 0.005)^480 – 1)/0.005)
FV = $79,659.63
That is the final balance for (a) and then since it exceeds the goal amount of $70,000 that means, that yes, you can reach your goal! :)