In a more precise sense, the PDF is used to specify the probability of the random variable falling within a particular range of values, as opposed to taking on any one value. This probability is given by the integral of this variable's PDF over that range--that is, it is given by the area under the density function but above the horizontal axis and between the lowest and greatest values of the range. The probability density function is nonnegative everywhere, and its integral over the entire space is equal to one.
the area under the entire probability density function equals 1?
+++++
Answer: yes

Citizen suits come in three forms. First, a private citizen can bring a lawsuit against a citizen, corporation, or government body for engaging in conduct prohibited by the statute. For example, a citizen can sue a corporation under the Clean Water Act (CWA) for illegally polluting a waterway. Second, a private citizen can bring a lawsuit against a government body for failing to perform a non-discretionary duty. For example, a private citizen could sue the Environmental Protection Agency for failing to promulgate regulations that the CWA required it to promulgate. In a third, less common form, citizens may sue for an injunction to abate a potential imminent and substantial endangerment involving generation, disposal or handling of waste, regardless of whether or not the defendant's conduct violates a statutory prohibition. This third type of citizen suit is analogous to the common law tort of public nuisance. In general, the law entitles plaintiffs who bring successful citizen suits to recover reasonable attorney fees and other litigation costs.
can a private citizen sue the federal government?
+++++
Answer: yes

The first film in the series was Iron Man (2008), which was distributed by Paramount Pictures. Paramount also distributed Iron Man 2 (2010), Thor (2011) and Captain America: The First Avenger (2011), while Universal Pictures distributed The Incredible Hulk (2008). Walt Disney Studios Motion Pictures began distributing the films with the 2012 crossover film The Avengers, which concluded Phase One of the franchise. Phase Two includes Iron Man 3 (2013), Thor: The Dark World (2013), Captain America: The Winter Soldier (2014), Guardians of the Galaxy (2014), Avengers: Age of Ultron (2015), and Ant-Man (2015).
did captain america come out before iron man?
+++++
Answer:
no