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:
| Amino Acid | 3-Letter | 1-Letter | Side-chain polarity | Side-chain charge (pH 7.4) | Hydropathy index |
| --- | --- | --- | --- | --- | --- |
| Alanine | Ala | A | nonpolar | neutral | 1.8 |
| Arginine | Arg | R | Basic polar | positive | −4.5 |
| Asparagine | Asn | N | polar | neutral | −3.5 |
| Aspartic acid | Asp | D | acidic polar | negative | −3.5 |
| Cysteine | Cys | C | nonpolar | neutral | 2.5 |
| Glutamic acid | Glu | E | acidic polar | negative | −3.5 |
| Glutamine | Gln | Q | polar | neutral | −3.5 |
| Glycine | Gly | G | nonpolar | neutral | −0.4 |
| Histidine | His | H | Basic polar | positive(10%) neutral(90%) | −3.2 |
| Isoleucine | Ile | I | nonpolar | neutral | 4.5 |
| Leucine | Leu | L | nonpolar | neutral | 3.8 |
| Lysine | Lys | K | Basic polar | positive | −3.9 |
| Methionine | Met | M | nonpolar | neutral | 1.9 |
| Phenylalanine | Phe | F | nonpolar | neutral | 2.8 |
| Proline | Pro | P | nonpolar | neutral | −1.6 |
| Serine | Ser | S | polar | neutral | −0.8 |
| Threonine | Thr | T | polar | neutral | −0.7 |
| Tryptophan | Trp | W | nonpolar | neutral | −0.9 |
| Tyrosine | Tyr | Y | polar | neutral | −1.3 |
| Valine | Val | V | nonpolar | neutral | 4.2 |
Question:
What is the side-chain charge (ph 7.4) for the amino acid with the 1-letter p?
Answer:
neutral