(iii) To find the number of selections with exactly 2 Es and 2 Ns, we consider the letters in SEVENTEEN: S, E, V, E, N, T, E, E, N. We need to select 2 Es and 2 Ns, leaving 1 more letter to choose from S, V, or T. This can be done in 3 ways: EENN + S, EENN + V, EENN + T. Thus, there are 3 possible selections.

(iv) To find the number of selections with at least 2 Es, we consider the following cases:

1. 2 Es: Choose 2 Es and 3 other letters from S, V, N, T, N. This can be done in 7 ways: EENN + S, EENN + V, EENN + T, EENT + S, EENT + V, EENT + N, EENS + V.
2. 3 Es: Choose 3 Es and 2 other letters from S, V, N, T, N. This can be done in 7 ways: EEE + SV, EEE + SN, EEE + ST, EEE + VN, EEE + VT, EEE + NT, EEE + NN.
3. 4 Es: Choose 4 Es and 1 other letter from S, V, N, T. This can be done in 4 ways: EEEE + S, EEEE + V, EEEE + N, EEEE + T.

\(Adding these, the total number of ways is 7 + 7 + 4 = 18.\)