Fill in the blanks please i need help an object moving at the same speed and in the same direction is also experiencing forces. the object will not change speed or direction unless an force is applied.

Donald is studying the eating habits of all students attending his school. he samples the population by dividing the students into groups by grade level and randomly selecting a proportionate number of students from each group. he then collects data from the sample. which type of sampling is used? select the correct answer below: systematic sampling convenience sampling stratified sampling cluster sampling

The social contact theory states that

Statement best describes the main reason behind the establishment of government in the early river valley civilization‘s