URGENT PLEASE HELP If you answer this correctly ill answer some of your questions you have posted! (30pts)

What is the magnitude of the acceleration vector which causes a particle to move from velocity −5i−2j m/s to −6i+ 7j m/s in 8 seconds. answer in m/s.

Individuals who live below the poverty line get seriously ill more often than those who do not what could be the hidden variable in this situation?

Which of the following is a measure of the amount of light a star directly emits?               a.  luminosity    b.  intensity    c.  wavelength    d.  brightness