Physics question for brainliest < 3

Experiment scenario 2: a biology student wants to conduct a study of how the amount of food affects the weight gain for mice. i have set up four cages with a mouse in each cage. fill in the boxes that would allow the biology student to complete the study correctly

The a metal retainer that keeps the rolling elements evenly spaced. n a. seal n b. separator n c. bearing n d outer race

Asap time is ! best answer gets compose at least one well-developed paragraph on the following: define the term concurrent powers, and give an example of a concurrent power of government.