What will be the effect—understated (U), overstated (O), or no effect (N)—on the income of the present and future periods if the following errors were made? In all cases, assume that amounts carried over into 20X1 would affect 20X1 operations via the routine accounting entries of 20X1.

Period 20X0 20X1 1. Revenue has been collected in advance, but earned amounts have not been recognized at the end of 20X0. Instead, all revenue was recognized as earned in 20X1 2. Revenue for services rendered has been earned, but the unbilled amounts have not been recognized at the end of 20x0. 3. Accrued wages payable have not been recognized at the end of 20Xo. 4. Prepaid rent has been paid (in late 20x0), but no adjustment for rent used in 20X0 was made. The payments have been debited to prepaid rent. They were transferred to expense in mid 20X1