Which of the following statements are $CORRECT$ when a protein sequence database is searched using the $BLAST$ algorithm?

1. A larger E-value indicates higher sequence similarity
2. E-value $<10^{-10}$ indicates sequence homology
3. A higher BLAST score indicates higher sequence similarity
4. E-value $>10^{10}$ indicates sequence homology
1. $P, Q$ and $R$ only
2. $Q$ and $R$ only
3. $P, R$ and $S$ only
4. $P$ and $S$ only