deliberately indifferent to his safety. See Farmer v. Brennan, 511 U.S. 825, 835-39, 843, 114 S.Ct. 1970, 128 L.Ed.2d 811 (1994) (explaining that a prison official is not liable for failing to protect one inmate from another unless the prisoner shows that he was housed under conditions that posed a substantial risk of serious harm, and that the prison official acted with deliberate indifference to the prisoner’s safety). The district court properly dismissed Yoon’s retaliation claims. Yoon alleged no facts to establish that his transfer from one prison yard to another, or his celling with particular individuals, were adverse actions, nor that his First Amendment activity motivated the two teachers who allegedly harassed him. See Rhodes v. Robinson, 408 F.3d 559, 567-68 (9th Cir.2005) (<HOLDING>). The district court also properly dismissed
holding that for a retaliation claim to be viable a prisoner must allege inter alia that a state actor took adverse action against him because of his protected conduct holding that to establish a causal connection plaintiff must show that the individual who took adverse action against him knew of the employees protected activity holding in the title vii context that the plaintiff must show that the individual who took adverse action against him know of the employees plaintiffs protected activity holding that the plaintiffs failure to set forth a time frame in which his protected activity and the adverse action took place precluded an inference of a causal relationship between them and warranted dismissal of his first amendment retaliation claim holding that state action occurs when inter alia the party charged with the deprivation is a person who may fairly be said to be a state actor