Whether Ben can make an action of negligence against the supermarket, or not?
Negligence can be best defined as a contravention of an owed duty of care, particularly due to presence of foreseeability of loss/ harm. Where person caries on such a work, where there are chances of his work harming the other party, such person owes a duty of care to the other party, by carrying on the work in a manner, where such other party is not harmed (Martin & Lancer, 2013). Through Donoghue v Stevenson  UKHL 100, it was established that a duty of care is owed to the consumers by the manufacturers, as the acts of manufacturers can injure the consumer, owing to proximity between them and reasonable foreseeability of losses. In case the same takes place, the aggrieved party can apply for damages, for the harm or loss sustained by them. These can be for physical, psychological or economic losses (Lunney & Oliphant, 2013).
Often in the cases of negligence, a defence of contributory negligence is cited, where the party is deemed to contribute towards the injuries sustained by them. When a case of contributory negligence is present, the aggrieved party gets a reduction in their awarded damages (Latimer, 2012). Raad v KTP Holdings Pty Ltd as Trustee for VM and KTP Nguyen Family Trust  NSW 2016 888 was a case where the damages were brought down by 10% owing to the plaintiff running on wet tiles (Devitt, 2016).
In the given case study, Ben was a consumer and as per the case of Donoghue v Stevenson, the supermarket owed a duty of care to Ben, as there was proximity and reasonable foreseeability. There was proximity as Ben came to shop in the supermarket, which made it a duty of the supermarket to provide safe shopping experience to its customers. Also, it was reasonably foreseeable that a person would slip on wrapping paper, as that is not something which belongs on floor. As supermarket failed in doing so, they would be liable to compensate Ben for his loss, owing to their negligence. This loss would be for his medical bills, and also for his lost opportunity to swim.
However, Ben contributed to his injuries by not paying attention to the floor and being busy on the phone. So, based on Raad v KTP Holdings Pty Ltd as Trustee for VM and KTP Nguyen Family Trust, the damages awarded to Ben would be brought down.
Hence, Ben can make an action of negligence against the supermarket in a successful manner.
Whether Ben can make an action of negligence against Sam, or not?
The risk of harm has to be taken as would a reasonable person would take, as per the case of Wyong Shire Council v. Shirt (1980) 146 CLR 40. So, foreseeability of harm depends on the view of a rational person (Jade, 2017).
Sam and Ben were two people in the supermarket and they had proximity between them, where actions of one could affect another. However, Sam or any other reasonable person, as per Wyong Shire Council v. Shirt, could not have foreseen that by helping Ben, he would further be injured.
Hence, the lack of reasonable foreseeability means that Ben cannot make an action of negligence against Sam.
Devitt, S. (2016). A slip up - shopping centre liable for slip and fall on wet tiles. Retrieved from: https://www.lexology.com/library/detail.aspx?g=bdcef724-3c2e-482d-9d74-540bc1a44d6c
Jade. (2016). Wagon Mound (No. 1) -- "The Oil in the Wharf Case". Retrieved from: https://h2o.law.harvard.edu/collages/4919
Latimer, P. (2012). Australian Business Law 2012 (31st ed.). Sydney, NSW: CCH Australia Limited.
Lunney, M., & Oliphant, K. (2013). Tort Law: Text and Materials (5th ed.). Oxford: Oxford University Press.
Martin, J., & Lancer, D. (2013). AQA Law for AS Fifth Edition (5th ed.). Oxon: Hachette UK.