European countries were building powerful navy's before world war 1 this is

Mr. mann's science students were experimenting with speed. they set up a 1 meter (100 cm) track. the students used balls instead of cars. the balls were different sizes and made of different materials. four at a time, students rolled balls around the track to see which had the fastest and slowest speeds. some of their data are shown in the table. which ball will take the longest to complete one lap around the track?

Identify three different reasons of why people have had to migrate and give examples to justify your reasons. use 3-6 sentences to explain your response.

Plz 20 ! in a citizens elect the president as head of government separately from the legislature? a: parliamentary democracy b: communist state c: presidential democracy d: autocratic state