Does anyone know about this : applying the parallelogram of forces law. or does anyone know of any notes about diagrams and formula?

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

6. an article, which costs rs. 850 is sold at a profit of 6%.what is the selling price ? -a) rs.900 b) rs. 901 c) rs. 890 d) rs. 905

The index of refraction of the oil is 1.20. what is the minimum thickness t of the oil slick at that spot?