Please read the following table in Markdown format and then answer the question according to the table. Table cells in one row are seperated by '|', and different rows are seperated by '
'.

Table:
| IEC\nWorld Plugs\nType1 | Standard | Power\nrating | Earthed | Polarised | Fused | Insulated\npins | Europlug\nCompatible |
| --- | --- | --- | --- | --- | --- | --- | --- |
| A | NEMA 1-15 unpolarised | 15 A/125 V | No | No | No | No | No |
| A | NEMA 1-15 polarised | 15 A/125 V | No | Yes | No | No | No |
| A | JIS C 8303, Class II | 15 A/100 V | No | No | No | No | No |
| B | NEMA 5-15 | 15 A/125 V | Yes* | Yes | No | No | No |
| B | NEMA 5-20 | 20 A/125 V | Yes* | Yes | No | No | No |
| B | JIS C 8303, Class I | 15 A/100 V | Yes* | Yes | No | No | No |
| C | CEE 7/16 (Europlug) | 2.5 A/250 V | No | No | No | Yes | Yes |
| - | CEE 7/17 | 16 A/250 V | No | No2 | No | No | Yes |
| - | GOST 7396 C 1 | 6 A/250 V\n16 A/250 V | No | No | No | No | Yes |
| - | BS 4573 | Socket\n0.2 A/250 V\nPlug\nUnspecified7 | No | No | No | Yes | No |
| D | BS 546 | 2 A/250 V\n5 A/250 V\n15 A/250 V\n30 A/250 V | Yes | Yes | Optional | Optional | No |
| E | CEE 7/5 ‡ | 16 A/250 V | Yes* | Yes4 | No | No† | Yes |
| F | CEE 7/4 Schuko ‡ | 16 A/250 V | Yes* | No | No | No† | Yes |
| G | BS 1363, IS 401 & 411, MS 589, SS 145 | 13 A/250 V | Yes | Yes | Yes | Yes | No |
| H | SI 32 | 16 A/250 V | Yes5 | Yes | No | No | Yes |
| - | TIS 166-2549 | 16 A/250 V | Yes | Yes | No | Yes | Yes |
| I | AS/NZS 3112 | 10 A/240 V\n15 A/240 V\n20 A/240 V\n25 A/240 V\n32 A/240 V | Yes* | Yes | No | Yes | No |
| I | CPCS-CCC | 10 A/250 V | Yes | Yes | No | No | No |
| I | IRAM 2073 | 10 A/250 V | Yes | Yes | No | No | No |
| J | Swiss SEV 1011 | 10 A/250 V\n16 A/250 V | Yes* | Yes | Optional5 | Optional6 | Yes |
| K | Danish 107-2-D1 | 13 A/250 V | Yes* | Yes | No | No | Yes |
| L | CEI 23-16/VII | 10 A/250 V\n16 A/250 V | Yes* | No | No | Yes | Yes |
| M | South Africa SABS 164-1 | 16 A/250 V | Yes | Yes | Optional | Optional | No |
| N | Brazilian NBR 14136 (2 pin) | 10 A/250 V\n20 A/250 V | No | No | No | Yes | Yes |
| N | Brazilian NBR 14136 (3 pin) | 10 A/250 V\n20 A/250 V | Yes* | Yes | No | Yes | Yes |
| N | South Africa SABS 164-2 (2 pin) | 16 A/250 V | No | No | No | Yes | Yes |
| N | South Africa SABS 164-2 (3 pin) | 16 A/250 V | Yes* | Yes | No | Yes | Yes |
Question:
how many different types of world plugs are earthed?
Answer:
18