Fix a conductor and a prime p$p$. Then
Do the elliptic curves in the same isogeny class after reduction modulo p$p$ have the same number of points over the finite field $F_{p} ?$$\mathbb{F}_{p} ?$
Do the elliptic curves belonging to two different isogeny classes corresponding to the fixed conductor, after reduction modulo p$p$ have the same number of points over the finite field $F_{p} ?$$\mathbb{F}_{p} ?$