Four conjectures on the numbers p, 2p-1, 3p-10 and np-n+1 where p prime

In this paper I make the following four conjectures: (I) there exist an infinity of primes p such that 3*p – 10 is also prime; (II) there exist an infinity of triplets of primes (p, 2*p – 1, 3*p – 10); (III) there exist an infinity of primes q obtained concatenating a prime p to the right with 2*p – 1 and to the left with 3 (example: for p = 11, q = 31121, prime; (IV) there exist, for any n positive integer, n > 1, an infinity of primes q obtained concatenating a prime p to the right with n*p – n + 1 and to the left with 3 (examples: for n = 5 and p = 19, q = 31991, prime; for n = 8 and p = 13, q = 31397, prime).