Two blocks each of mass m = 4.10 kg are fastened to the top of an elevator as in the figure below.

(a) If the elevator accelerates upward at 1.6 m/s2, find the tensions T1 and T2 in the upper and lower strings.
T1 ? N
T2 ? N

(b) If the strings can withstand a maximum tension of 104.0 N, what maximum acceleration can the elevator have before the first string breaks?
? m/s2