Hi everyone, I am seeking help regarding the graphs for analytic and numeric solutions and their errors separately?

graph_for_error_.mw

I Have drawn a contour graph for my problem. I am looking for help on how to change the colours between every two lines according to desire. Or how can I use different colours like rainbow etc? 

Countour_colouring_help.mw

I am looking for help regrading change of colours between contours lines, means if there is 10 countour lines, then the gap between two line have different colour then other. Atleast repeat  colours scheme after 7 colours like rainbow combination.....As e reference please check this picture

Hi everyone, Could anyone help me to draw horizontal and vertical line in a plot? Also, How to add command for legends to show inside the plot at empty space. I every time edit legends in paint manually. For reference, I am attaching a picture

Help_graph_and_legends_place.mw

Hi every one, I am trying to find a relation from an equation by putting it is equal to zero but could not get the solution.

Solution_of_an_Equation.mw

Hi all, I am trying to draw a streamline for an ODE, but my worksheet is not working. Could anyone please have a look and help regarding the removal of the error? The value of unknown parameters such as k can be fixed randomly like 0.1,0.2 ,0.3 etc ?

Help.mw