What are good examples of (open source) existing citizen science tools for mapping locations of interest either web or mobile?

Match the personality traits with their description

Knowing that the central portion of link bd has a uniform cross sectional area of 800 mm2 , determine the magnitude of the load p for which the normal stress in link bd is 50 mpa. (hint: link bd is a two-force member.) ans: p = 62.7 kn

When early motion pictures played in movie theaters, they were often accompanied by live organ or piano music. which of the following are the most likely reasons that this happened? (select all that apply). the music was provided to distract audience members from the loud sounds made when filmstrips were changed. the music accompanied the movies because the movies were silent and audiences were used to hearing music during plays in theaters. the music usually was played before, and sometimes after the movie, as an alternative form of entertainment. the music viewers to interpret the dramatic action in the films.