In studies about new medicines, researchers usually give one group of patients the medicine that is designed to treat an illness. They give another group of patients a placebo, which is taken the same way as the medicine but does not actually contain the ingredients of any medicine. Different medicines are tested in different experiments, but the placebos usually contain the same non-medical ingredients. If both groups of patients are healed, then researchers cannot be sure whether the medicine caused improvement, but if the group given the medicine is healed while the group given the placebo remains ill, researchers can conclude that the medicine causes the illness to go away. In medical experiments, which group receives placebos? the experimental group the control group both the experimental and control groups neither the experimental nor control group

Plz me ! 1 which of earths spheres contains most of its mass? a atmosphere b hydrosphere c geosphere* d biosphere 2 erosion and weathering are examples of which types of forces? a constructive forces b destructive forces* c gravitational forces d inertia-related forces 3 which of the following statements about earths atmosphere is true? a earths atmosphere contains 78% water vapor which is essentail to life b earths atmosphere contains 21% oxygen c earths atmosphere contains carbon dioxide which all life forms require d earths atmosphere allows radiation from the sun to pass through it and warm earths surface* 4 the strenght of the force of gravity between two objects is determined by which of the following factors? select all that apply a the messes of the objects* b the distance between the objects* c the volumes of the objects d the surface area of the objects 5 earth and moon are kept in there respective orbits due to the influence of a inertia b gravity c gravity and inertia* d neither gravity or inertia if you answer all questions right i will give

Juju.01) 5 geologic events a group of students designed an experiment in an ice rink to represent the solar system. the steps of the experiment are listed below. 5: geologic events 1. choose a student to represent the sun. the planets are represented by two tennis balls. 2. ask the student to hold the tennis balls in each palm and spin on the ice with arms stretched out. 3. ask the student to draw in the arms after about 10 spins. 4. observe the student's arms rotate faster when they are closer to the body. 05 geologic events enors) the experiment most likely demonstrates that (2 points) 07 discussion-based sessment/module planets exert gravitational force on the sun the sun exerts gravitational force on the planets 3.07 discussion-based ssessment speed of a planet depends on its distance from the sun new version available! (3.0.119) get it now submit 18.07: module exam description

Just on number 2 (all parts), and if you do answer explain in detail