The elements of negligence are: (1) defendant's duty to conform to a certain standard of conduct for the protection of others against unreasonable risks; (2) a breach of the duty by failure to conform to that standard; (3) a causal connection between the defendant's conduct and resulting injuries; (4) actual loss or damages. (Prosser & Keeton on Torts, 30, pp. 164-165.) To determine the standard of conduct required by the first element we generally undertake a risk-benefit analysis "by balancing the risk, in the light of the social value of the interest threatened, and the probability and extent of the harm, against the value of the interest which the actor is seeking to protect, and the expedience of the course pursued. For this reason, it is usually very difficult, and often simply not possible, to reduce negligence to any definite rules; it is 'relative to the need and the occasion,' and conduct which would be proper under some circumstances becomes negligence under others." (Id. at 31, p. 173.)